LIBRARY OF CONGRESS 



Shelf ...3 



^UNITED STATES OF AMERICA. 



BOILER MAKING 



BOILER MAKERS. 

A PRACTICAL TREATISE ON WORK IN 
THE SHOP. 

SHOWING THE BEST METHODS OF 

RIVETING, BRACING, AND STAYING, PUNCHING, 
DRILLING, SMITHING, Etc. 



THE MOST ECONOMICAL MANNER OF OBTAINING 
THE BEST QUALITY OF OUTPUT AT • 
THE LEAST EXPENSE. 

/bv 

Y BY 

W. H. FORD, M.E. 



1' 



if-3/ 



/•: N cy oFco/v n i-. 



NEW YORK: 

JOHN WILEY & SONS, 
15 Astor Place. 

1887. 




/ 



T J 



Copyright, 1887, 
By John Wiley & Sons,, 



I 



3j /»7 






CONTENTS. 



CHAPTER PAGE 

I. Materials 9 

II. Testing Materials 14 

III. Boiler Forms, 20 

' IV. Riveted Joints 44 

V. Bracing and Staying 58 

VI. Flanging 92 

VII. Welding Plate 108 

VIII. Annealing 115 

IX. Smithing 121 

X. Punching 138 

XI. Drilling. 150 

XII. Trimming 155 

XIII. Cold Bending. 159 

XIV. Setting Up 164 

XV. Calking 175 

XVI. Tube Setting 181 

XVII. Fittings 189 

XVIII. Testing 196 

XIX. Ordering Stock 204 



PREFACE. 



Shortly after entering the profes- 
sion of mechanical drafting, I was 
given a boiler to design. That is to 
make a working drawing. I had been 
taught the principles as to the capacity 
or size in relation to the power, the 
thickness of shell required to resist 
the strains, and other such generalities 
which relate to types and relative 
economy, but barely a hint was given 
me as to the multifarious small details 
which go -to make up the difference 
between work made for sale and that 
made for service. 

In consequence of my iack of knowl- 
edge, I was compelled to consult the 



foreman boiler-maker oftener than I 
should. He being as kind as he was 
experienced, generously gave me the 
required information for that boiler. 
This of course not being sufficient for 
my wants, I set about looking for works 
on the subject. My disappointment was 
great, indeed, to find that among the 
very few books on the subject, there 
were absolutely none which gave the 
information that I desired. Such as 
were complete buried themselves over 
neck and ears in abstruse formulas 
which it is doubtful if the authors could 
solve after a month's absence from the 
work, 

I commenced making notes of any 
and every thing on the subject ; not 
only the details, but the methods of 
making them. Having shown my notes 
to a foreman boiler-maker he advised 
me to write them out, and have them 
printed, for it was just such matter as 
every boiler-maker wanted. This hav- 
ing been done and shown to several 



PREFACE. 7 

boiler-makers, further encouragement 
was given to go ahead. 

If any should ask, why the power or 
capacity and economy of boilers is not 
touched upon, I would say that that is 
strictly in the field of Engineering, 
which apparently is well filled, while 
this book is entirely devoted to the 
Workshop. At the same time it is to be 
hoped that some engineers, at least those 
just entering into the workaday world, 
may find something that will help them 
while relieving the boiler-makers of 
many disagreeable and difficult con- 
structions. Again it may be asked why 
then I introduce strength of materials 
and such matters. In answer I would 
say that nine out of ten drawings sent 
to the shop, leave such things entirely 
to the boiler-makers, who, more than 
half of them, have no time to study 
Rankine or mathematical science, even 
were they so disposed. 

The endeavor, in this work, is to 
make it one of ready reference, at the 



same time enabling one to work out for 
himself, in a simple way such problems 
as would naturally come up in the 
course of his daily work. 

W. H. Ford. 
December 23, 1885. 



MATERIALS. 

Practically, wrought iron and steel 
are the only metals used in boilers. 
Some few have brass or copper tubes 
where wood is used for fuel. Copper 
fireboxes have long, been discarded in 
this country. The extra thickness re- 
quired for strength as well as to allow for 
the rapid deterioration caused by the 
action of coal gasses more than mak- 
ing up for its greater power of con- 
duction. 

In boiler plates the quality of tensile 
strength should not be the sole con- 
sideration. The mere fact that a piece 
of unworked plate, pulled apart in a 
testing machine, resisted so many thou- 
sand pounds, is no proof that it will 
withstand the various processes of flang- 



IO BOILER MAKING. 

ing, punching, bending, etc., in the 
shop, nor the constant and varying 
strains, from heat and cold, in service. 
Ductility and toughness are as essential 
qualities as great tensile strength. 

"Steel'' plates should have a tensile 
strength of 55,000 to 60,000 pounds per 
square inch of section. If the strength 
goes much beyond this the excess of 
carbon required to produce it causes 
brittleness and makes it difficult to 
work. In a test piece, four inches long, 
the elongation should be not less than 
25 per cent. Boiler steel goes under 
various names or brands, each maker 
having his own, and claiming special 
points of excellence for each. How- 
ever, nearly all will meet the above 
named requirements. 

Iron plates have several brands, not 
peculiar to any one maker, but used by 
all, that are intended to indicate the 
quality. These are : 

C. H. No. 1, Firebox, 
C. H. No. 1, Flange, 



MATERIALS. II 

Shell, 

Refined, and 
Tank, 

C. H. No. i Firebox and C. H. No i 
Flange are made entirely of charcoal 
iron. The C. H. No. i Firebox is 
somewhat harder than the Flange, so as 
to resist more effectually the fierce heat 
of the fire. They should stand from 
50,000 to 55,000 pounds tensile strain in 
any direction if the makers use the 
brand honestly. 

" Shell " iron has but very little char- 
coal iron in its composition and that as 
a skin. It cannot be flanged. Neither 
can it be bent across the grain. It 
should stand, with the grain, 45,000 to 
50,000 pounds ; while across the grain 
35,000 is good. 

" Refined ' is rather a doubtful term, 
and really means that the iron is refined 
from the pig It may be that it is sim- 
ply muck bar or that it is a fair quality, 
which has undergone several workings. 

The actual quality is best determined 



12 BOILER MAKING. 

by the price. The more the iron is 
worked the better it is and of course the* 
greater the price. 

"Tank " iron is a poor quality which 
will hold water, but not under much 
pressure. It cannot be flanged. With 
the grain in light plates it can be bent 
to about a four inch radius. 

There are special brands of extra 
good qualities of iron such as Sligo, N. 
P. U., Eureka and Pine. These are 
almost the same as the so-called homo- 
geneous steel in their composition. 
The tensile strength is the same, but 
the percentage of elongation is less, 
about 15 to 20 per cent 

If there are no means of determining 
the strength of plates in boilers, the U. 
S. Government inspectors rate them at 
45,000 pounds to the square inch. The 
maker should always brand the plates 
with his name and the amount of tensile 
strain he thinks it will safely bear. 
This brand should always be placed in 
the boiler in such a position that it can 



MATERIALS. 1 3 

readily be found. Boiler- makers not 
having a testing machine of their own, 
-should require a guarantee of the plate 
makers. This should be kept, and an 
accurate record made of the disposition 
of the plate described by it. 

Iron for stay bolts should be of the 
very best, strong, tough and ductile. 
It should show a tensile strength of not 
less than 48,000 pounds per square inch, 
and have an elongation of at least 28 per 
cent, in a 4-inch specimen. It should 
cut a clean thread with the dies in fair 
condition. 

For rivets, it is important that the 
metal .should possess the qualities of 
toughness and ductility in the highest 
degree. An immense strain is thrown 
upon them by their contraction in cool- 
ing, when sooner or later, if the metal 
is short or brittle, they will snap with 
more or less dangerous result. At 
present rivets are mostly made of iron, 
but steel seems to be the coming metal. 
Already the British Admiralty have 



14 BOILER MAKING. 

demanded it, and are using it with good 
results. It is required to be of a tensile 
strength of 58,000 to 67,000 pounds per 
square inch and have an elongation of 
not less than 20 per cent, in a length of 
8 inches. 

Iron for stay rods should be of good 
quality, having a tensile strength of not 
less than 40,000 pounds per square 
inch. 

Cast iron is used in boiler work to a 
very limited extent. It makes very 
good thimbles and feet for crown bars, 
frames and covers for man and hand 
holes. It is sometimes used for the 
heads of plain cylindrical boilers. But 
it is rather unreliable and should never 
be used where its tensile strength is to 
be depended upon. 

II. 

TESTING MATERIALS. 

As soon as possible after receiving a 
lot of material it should be closely ex- 
amined and tested for size and sound- 
ness. There are so many chances of 



TESTING MATERIALS. 1 5 

error in size, and of defects that may 
condemn, that to avoid delay and ex- 
pense the sooner such are discovered 
the better. All material should be test- 
ed for tensile strength. 

The thickness of plates should be 
particularly looked after. If it is over 
5 per cent, less than the thickness called 
for it should be rejected, as it will mate- 
rially affect the strength, as well as be 
an aggravation to fit. An excess of 5 
per cent, should also cause rejection, or 
at least a rebate on cost to the amount 
due for over weight. Examine the sur- 
face and edges thoroughly for lamina- 
tions, blisters and other flaws, such as 
cracks, indentations or marks caused by 
careless rolling. To determine its in- 
ternal soundness, set it up on edge and 
. go over it carefully with a light hammer. 
If the blow gives a sharp, ringing sound, 
the plate is good, but if it is dull and 
heavy in character, it indicates a defect. 
To be sure of trying all parts of the 
surface the plate may be lined off into 



1 6 BOILER MAKING. 

squares of four to five inches. To still 
further test the soundness, it may be 
slung by the corners horizontally, and 
strewn with dry sand. On being lightly 
tapped underneath, the sand will be 
thrown off where the plate is solid, but 
will remain fixed where a blister or lami- 
nation occurs. While this is being done, 
a strip from the edge should be tested 
for tensile strength. 

If the plate passes the foregoing, it 
should then be subjected to the work- 
ing tests. A strip should be taken from 
the plate, i| to 2 inches wide, and bent 
cold over the corner of an anvil. This 
corner should not be of more than y 2 
inch radius. A % inch plate of good 
iron should bend, with the grain, to an 
angle of 90 degrees -without cracking, 
and across the grain to an angle of 55 
degrees. The angle for heavier plates 
will be as per table : 

Thickness of plates..^, 5-16, %, 7-16, J4 %, %, % t 1. 
To bend across the 

grain to (degrees).. 55, 52, 49, 46, 43, 37, 31, 25, 20. 
To bend with the 

grain to (degrees) .90, 85, 80, 75, 70 60, 50, 40, 30. 



TESTING MATERIALS. 1 7 

Flange iron, when heated to a bright 
red, should bend double without crack- 
ing at the edges. 

Steel should bend double when cold 
and at a cherry red heat. Also after 
being heated to a cherry red and cooled 
in water at a temperature of 80 degrees. 

' 1 

i! 




Fig. 1. 

The parts hammered down so that day- 
light cannot be seen between them. 
Be careful in heating steel to bring up 
the heat slowly. A quick fire is apt to 
burn the surface before the centre is 
fully heated. If the metal will bear 
these tests without cracking at the 



i8 



BOILER MAKING, 



edges, it shows a very good quality that 
will work well and easily. Bending can 
be done more successfully by striking a 
glancing blow. See figure i. 

Tubes should be examined for seams, 
flaws in the welding and flat spots. As 
they are subjected to external pressure 
this last is a fatal defect. Being thin 
they are very easily flattened and should 
be carefully handled. A tube should 
stand expanding tightly in a hole 1-16 
inch larger than itself, and the edge 
turned over without cracking trans- 
versely or splitting. A good test is to 
take a short piece say 1^ inches long, 
where the tube is 2 inches outside 
diameter, and hammer it down flat as in 
figure 2. When down solid it should 




Fig. 2. 



TESTING MATERIALS. 



19 



show no transverse cracks and but 
slight splitting. 

Staybolt iron, beside testing for 
tensile strength, should also be tested 
by bending double till the two parts 
meet It should then show no cracks. 

Rivets are seldom tested for tensile 
strength. About one in a hundred are 
usually taken for forge testing. They 
should stand bending cold to the shape 
shown in figure 3. The space a to be 




Fig. 3. "Fig. 4. 

not over one diameter of the rivet. 
Bent hot they should close the parts 
together. In neither case should they 
show a crack. No cracks should ap- 
pear on the edge of the head when 



20 BOILER MAKING. 

flattened out, hot, to y% inch thick, as in 
figure 4. 

III. 

BOILER FORMS. 

The forms of boilers and their parts 
are various, though composed mostly 
of cylinders or combinations of other 
forms with cylinders. The cylinder 
being the only form adapted to the 
purpose that is inherently self-sus- 
taining. 

While the sphere is the strongest 
form into which metal can be shaped to 
withstand a pressure that is equal in all 
directions, the practical difficulties of 
construction preclude its use entirely 
for boilers. Compared with a cylinder, 
in which the length equals the diameter, 
the sphere has about the same amount 
of available heating surface ; while the 
cubic contents is one-third less. 

Next to the sphere in strength comes 
the cylinder with hemispherical ends, or 



BOILER FORMS. 21 

egg-ends as they are called in England. 
These ends are costly and difficult to 
make, and as the flat ends are very 
readily stayed, they are far more 
preferable. 

To find the thickness of a hollow 
cylinder to withstand an internal pres- 
sure take : 

£>XP , 
* /= XK i 

2 C 

in which /=thickness in inches, 
Z>=diameter " " 
P— pressure per square inch 

in pounds, 
r=tensile strength, per square 

inch of section, 
K= factor of safety. 

This factor of safety is an arbitrary 
figure, for which in boiler-making 6 is 
usually taken. This nominally makes 
the boiler six times as strong as it really 
needs to be, but as it is used in this 
case, it only applies to the strength of 
the plate and is intended to cover the 
weakening effect of bad workmanship, 



22 BOILER MAKING. 

flaws and riveted joints. The strength 
of these joints ranges from 80 per cent, 
of the solid plate down to as low as 50 
per cent. 

The strength of a cylinder to resis- 
bursting may be found by taking : 
2 txc 
S=- 2 

The thickness t is taken twice be- 
cause there are two sides of the cylinder 
to resist the pressure. Take any op- 
posite points as a b in figure 5. Now the 
total pressure to be resisted at these two 
points, for a section 1 inch long, is the 
pressure per square inch multiplied by 
the distance they are apart in a straight 
line, (or the diameter). 

Fig. 5 




BOILER FORMS. 23 

To prove that this strain is due to 
the diameter and not to the circumfer- 
ence, take a c b in figure 6, as one-half 



Fig. 6 




of the cylinder. Divide the diameter 
into a number of equal parts. Draw 
parallel lines at right angles to a b f 
from a c b. These lines show the direc- 
tion of the force tending to rupture the 
plate at the points a and b. Now ex- 
tend these lines beyond a b, making 
them all of a length, by scale, equal to 
the pressure in lbs. per square inch. 



24 BOILER MAKING. 

Then if the sum of these lines in 
pounds per square inch be multiplied by 
the distance in inches between them, 
the answer will be, as before stated, the 
total amount to be sustained by the two 
sides. 

For the strength of a cylinder to resist 
the force tending to rupture it trans- 
versely take : 

CxtXc 

S= 3 

F 
in which C=circumference in inches. 
And for the force F take : 

F=AXP.\... 4 

in which F— force 

• y4=areaofend. 

A short calculation will show at 
once, that if the cylinder is strong 
enough to resist a diametrical force, 
that it will be several times strong 
enough to resist a longitudinal one. 

It must be remembered that flat ends 
require thorough bracing, which will be 
considered in full under the head of 
*' Bracing, and Staying." 



BOILER FORMS. 



25 



While an internal pressure tends to 
produce and' retain a circular, or more 
properly, a spherical shape, an external 
pressure has a directly opposite ten- 
dency. Therefore cylindrical flues and 
tubes to be self-sustaining under ex- 
ternal pressure must be truly circular in 
section. If not so, the only dependence 
for resistance to the pressure is the 
stiffness of the plate. For example take 
a 30 inch diameter flue, which has been 
flattened so that it forms an oval, like 
figure 7. 

Fig. v 




It will be readily seen that the total 



26 BOILER MAKING. 

pressure upon the flue on the long side 
is thirty-two times the pressure per 
square inch; while upon the short side 
the total pressure is twenty-eight times 
the pressure per square inch. Now if 
the pressure was 100 pounds per square 
inch, then the preponderance of pres- 
sure = (32 — 28) X 100 or 400 pounds. 
To resist this 400 pounds, we have only 
the stiffness of the plate from a to b. 
If this 400 pounds should spring the 
plate in the least, it would add to itself 
and take away from the short side as 
much, and this in a constantly increas- 
ing ratio, so that it would tal^e but a 
short time to collapse the flue. In this 
example the flue is supposed to have 
no end support or stiffening rings, which 
materially aid it to resist distortion. 

A longitudinal lap joint should be 
avoided, as the lap cannot be made 
without destroying the symmetry of the 
circle. A butted and welted joint is the 
proper one, because with it, the cylin- 
der is as near perfect in its shape as it is 



BOILER FORMS. 27 

possible to make it, and is almost en- 
tirely independent of the welt for help 
in preserving its form. About the only- 
duty of the welt is that of a ''stop- 
water," and for this a single one placed 
outside is sufficient 

For the thickness of plate in cylindri- 
cal flues, where the length does not 
exceed fifteen times the diameter, 
take: — 



-./■ 



LX&XP 



806,300 ' " D 

in which L= length in feet. 

More properly and in accordance with 
an exhaustive series of experiments by 
Sir, Wm. Fairbairn, it should read: — 



t = j/' 



LXDXP 



806,300 

But, as a factor of safety of five or 
six is or should be allowed, the former 
is sufficiently accurate and is far simpler. 

The transverse joints of flues should 
be made by flanging out the ends of the 



28 



BOILER MAKING. 



sections and riveting between them a 
solid forged ring as in figure 8. 

Fig. s 



— — J \ \mmm 



Fig. 9 



IPig.lO 



I 




This ring should not be less than ^ 



BOILER FORMS. 29 

inch thick, to allow for calking. Nor 
should the inside radius of the flange 
be less than twice the thickness of the 
plate, to allow for the difference of 
expansion of the flue and shell. 

Other methods of forming girth joints 
of flues are as shown in figures 9, 10, 
and 11. 

These are all very expensive to fit as 
they necessitate the greatest care in 
having the ends of the sections exactly 
the same diameter, and to have the rings 
drive on. If this is not done the joint 
will be an infinite source of trouble from 
the very first. Figure 11, although the 
most expensive of all, is an ideal joint, 
and is always used in extra high class 
work. Figures 9 and 10 do not allow 
for expansion, and should not be used 
unless other joints like 8 or 11 are used 
at least once in the same flue. Figure 
10, although often used, is very bad. 
Rolled tee-iron when bent, either hot 
or cold,is very apt to split at the root of 
the flange, and should be condemned al- 






30 BOILER MAKING. 

together for any purpose whatever in a 
boiler. In any of these joints, the ends 
of the plates should have not less than 
an inch between them to allow for calk- 
ing. 

Small lap-welded tubes are made 
much thicker than is required for 
strength to resist the pressure put upon ' 
them. The rapid wasting from corro- 
sion, and the wear from the sand blast 
action of the cinders, necessitating a 
much greater thickness. The difficulty 
of making a successful weld also keeps 
up the thickness. A very thin plate 
loses its heat too quickly. 

Fig. IS 




No dependence should be put upon 



BOILER FORMS. 3 1 

forms that are segments of cylinders, to 
sustain themselves. Such forms require 
staying as well as flats, although not 
in so great a degree. See figure 12, 
which is a common arrangement of the 
back connection in marine boilers. 

Where large openings are made in the 
shell of a cylindrical boiler, such as 
for manholes, domes, etc., compensating 
rings should be used to make up for the 
loss of section. It must be constantly 
kept in view that such openings take 
away that much of the cylindrical shape 
as well as throwing so much more labor 
upon- the adjoining portion of the plate. 

A good method of stiffening under a 
dome is by butting the barrel sheet on 

Fig. 13 




the same longitudinal centre. The out- 



32 BOILER MAKING. 

side welt being made wide enough to 
follow around the opening with a double 
lap and flanged up into the dome, as in 
figure 13. 

This welt should be 25 to 50 per cent 
heavier than the shell. The inner welt, 
which need not surround the hole, may- 
be made in. the usual manner. Figure 
14 shows a method largely used in 
locomotive boilers, which is not only 
a difficult job to fit and rivet up solidly, 
but is very unreliable. 

Fig. 14 



For domes where a large opening is 
not required for access to the boilers a 
good arrangement is shown in figure 15. 

Manholes should be oval and about 
15 or 16 inches long and 12 or 13 wide. 



BOILER FORMS. 7>3 

The long axis to be placed transversly 
to the boiler. The frame should be 



Fig. 15 




amply stiff to compensate for the part 
of the shell cut out, and should be in- 
side the boiler. The plate also should 
be inside and have two handles. The 
joint between plate and ring is better if 
faced, but this is not absolutely neces- 
sary when a rubber gasket is used, if it 
is fairly straight. 

Flat surfaces are not sufficiently self- 
supporting, unless made enormously 
thick. To find the thickness of a cir- 
cular head take: 



,=</ 



£>*XP 



This shows what a heavy plate is re- 
quired without allowance of a factor of 
safety. The best way is to allow it the 



34 BOILER MAKING. 

same thickness as is in the rest of the 
boiler and stay it, as if it had no strength 
or stiffness whatever. 

Heads of boilers should, wherever 
the design permits of it, have the flange 
turned inward so that they can be calked 
on both sides. 

Fig. 16 



I— 



F= 



Rectangular boilers with their great 
expanses of flat surfaces are fast be- 
coming obsolete. The pressures used 
of late years being too great for them 
without overloading them with braces 
and bars, till they are almost inaccessi- 
ble for cleaning out and repairs. The 
circulation also is badly obstructed. 

Furnaces are usually of the same 



BOILER FORMS. 



35 



general form as the shells. For cylin- 
drical boilers they are cylindrical. Their 
strength to resist pressure, , and the 
details of their joints, are the same as 
described for flues. In marine return 
tubular boilers they are connected with 
the tubes above them by a vertical flue 
called the back connection. See figure 
16. 

The longitudinal joints of these fur- 
nace flues should be entirely below the 
grates so as to keep them out of the in- 
tense heat of the fire. 



Fig. IV 




2,6 BOILER MAKING. 

Locomotive furnaces or fire-boxes, as 
they are commonly called, are mostly 
made with a flat or slightly arched 
crown, although quite a percentage 
have a semi-elliptic form, the latter 
being used with a straight top boiler, 
and the former with the raised wagon 
top. This raised wagon top gives con- 
siderable flat surface to stay, at the point 
a figure 18. Sometimes this flat sur- 

Fig.18 




face is gotten rid of by making the side 
of a large radius, say from one and one- 



BOILER FORMS. 



37 



half to twice the radius of the top, pro- 
ducing an Oval, in the fond hope of 
making it partially self-supporting. It 
only makes a neater appearance without 
enhancing its strength or stiffness to 
any practical amount. Nor as long as 
it is not a true circle, and a complete one 
at that, can it be done. The semi-elliptic 
crown is stayed with through bolts, the 
flat or slightly arched crown with gir- 
ders, except in the Belpair type (fig. 19) 

Fig. 19 




where the shell is brought down flat, in 
which through bolts are used. It is 
desirable in narrow water spaces, as at 
the sides of locomotive fire-boxes, and 
the back connections of marine boilers 



38 BOILER MAKING. 

that the space should be widened at the 
top as much as possible, so that the 
ascending steam which accumulates as 
it rises may have a greater freedom to 
escape into the steam-room without 
blowing the water out of the leg. 

Where the space is large enough, the 
bottoms of water legs are formed by 
flanging up a plate as in figure 20. 



-LA 



This method should not be attempted 
where the space is not sufficient to get 
a good sized holding-on hammer or 
block against the rivet. It is especially 
difficult in the narrow space allowed in 
locomotive boilers. For them the ar- 
rangement shown in figure 21 is used. 




inches thick, and because of the diffi- 



BOILER FORMS. 39 

culty in thoroughly upsetting the rivet 
at both ends; it should not be over 3 
inches wide. 

A width of two inches would be far 
better, and to provide for good circu- 
lation the space can be rapidly widened 
above.- Another plan is to flange the 
inside sheet in the form of an ogee 
to meet the outside one as in figure 22. 
iriig-. 33 




But this beside being difficult to calk 
well has the great disadvantage of groov- 
ing caused by deposits of sediment, 
which it is almost impossible to remove 
from the sharp angle between the plates. 
This deposit will rapidly harden and 
form a fulcrum for the plate to work 
upon, which is rapidy taken advantage 
of, and the plates become dangerously 
weak. Care must be taken to set the 
grates well above these joints, as the 



4° 



BOILER MAKING. 



intense heat of the fire will soon burn 
the heads off the rivets as well as the 
sheet if there is much accumulation of 
sediment. 

For furnace-doors, figures 26 and 21 
are used as well as figures 23, 24, and 
25 ; which are much better. Figure 25 
has proven to be the best of all, taking 
all things into consideration. 

Eig-. S3 



iFd<g<-. Q^t 



T 



Mg, 3-5 



A M- 



A I 



Figure 23 is the most convenient for 
working the fire, but gives more or less 



BOILER FORMS. 41 

trouble from grooving at a. Figure 24 
is entirely too deep for firing properly at 
the back end' and is costly and difficult 
to fit. 

Combustion chambers are often used 
in locomotive and other internally fired 
boilers, to allow the gases more time 
to become thoroughly ignited. They 
are sometimes formed of a brick wall, 
but oftener they compose a part of the 
boiler itself. 




Figure 26 shows the common practice 
in locomotive boilers. The intense 
heat playing upon the corner c produces 
so much steam, underneath that the 
water is driven away, leaving the plate 
unprotected ; and it rapidly burns out. 

Figure 27 is from a marine boiler, and 



42 



BOILER MAKING. 
Fig*. 3^7 




is so dangerous that it is given here 
only to s-how how badly a boiler can be 
designed. Figure 28 gives a good ar- 
rangement for a locomotive boiler in 
lieu of an arch, which forces the heat 
too sharply against the crown sheet. 











. 






p 




;^S^L-^^J^ 





By allowing a little space between the 
bricks and the tube sheet, the air which 
arises will materially aid the Combustion. 

The plates used for furnaces should 
be as thin as safety will allow, as heavy 



BOILER FORMS. 43 

plates will blister or burn when exposed 
to the intense heat, whereas if the plate 
is thin the water will absorb and carry- 
away the heat fast enough (other things 
being equal) to prevent such trouble. 
When a blister is once started there is 
no telling where it will end. As far as 
possible laps should be placed so that 
the currents of flame do not strike 
upon their edges. Care should be taken 
that there should be no places for the 
impurities of the water to lodge upon 
and bake. The water side of all lap- 
joints should be turned downward, and, 
as far as possible, above the water line. 



IV. 

RIVETED JOINTS. 

Riveted joints are made either by 
lapping or by butting the plates. The 
lap joint is the cheapest, but at the same 
time the poorest, as it distorts what 
would otherwise be a regular form. It 
may be made passably good, however, 
by bending the plates in opposite direc- 
tions so that the line of pull is directly 
through the centre of the lap and the 
faying surface as shown in figure 29. 

TPIg. 29 




This should be done whether the work 
is straight or cylindrical, except of 
. course girth seams on cylinders where 



RIVETED JOINTS. 45 

one course is made of larger diameter 
than its neighbor. Lap joints may have 
one or more rows of rivets, though sel- 
dom more than two. In cylindrical 
work the girth joints will be sufficiently 
strong with one row for all ordinary 
pressures, but the longitudinal joints 
should always be double riveted. 

Butt joints are usually double riveted, 
as in figure 30, the welts being of 





Fig. 30 






s 






i 




1 






>_ 






> 




| 







equal width. A much better joint is 
that shown in figure 31, which has the 

Fig; 31 



* 



outside welt double riveted, while the 
inside welt is narrower and takes but 
one row of rivets on each side the butt. 



46 BOILER MAKING. 

A very frequent fault in boilers is the 
grooving of the plates close against the 
edge of the lap on the inside, caused by 
the constant alternation of the expansion 
and contraction, that concentrates itself 
close to the stiffest part, which is the 
lap. This is also aided by bad calk- 
ing. Now in figure 30 we have a treble 
stiffness just at the edge of the lap; 
whereas in figure 31, which is as strong 
a joint as the plate will -stand, this stiff- 
ness is divided; thus lessening the ten- 
dency to buckle. The welts in figure 
30 should never be less than one-half 
the thickness of the plates they cover, 
and are usually the next sixteenth of an 
inch thicker. In figure 31 the outside 
(wide) welt should be three-quarters 

IFig.33 



1_ 



"\Z7 



\ / 

and the inside one-half the thickness of 
the plates. The space between the 



RIVETED JOINTS. 47 

rows of rivets should be about 25 per 
cent, more than that called for in the 
table, to allow for calking. 

There are other styles of welted 
joints, the most usual being as in figures 
32 and S3- Figure 32 is a vagary, though 

JFig. 33 

A 




often met with. It strengthens only 
one plate, while the other is as weak as 
ever, and the tendency to groove is 
greater than if the welt was not used. 
The welt in figure 33 is intended solely 
to prevent grooving, and for this pur- 
pose it is a comparative success. It is 
made of light iron, not over one-half the 
thickness of the plate, and is riveted 
with only one-half the number of rivets 
as the lap, if the lap is single riveted. If 
the lap is double riveted, use the same 
number as are in one row. 

In the designing of riveted joints, the 



40 BOILER MAKING. 

point to be aimed at is to have the 
strength of the rivets and that part of 
the plates left between the rivet holes as 
nearly equal as possible. The propor- 
tions of riveted joints given in the ac- 
companying table are compiled from the 
practice of several prominent and suc- 
cessful boiler manufacturers. The per- 
centages of strength given are figured 
from the formulae adopted by the United 
States Board of Supervisors of Boiler 
Inspectors. The excess of rivet strength, 
as shown, is made to allow for the 
almost unavoidable imperfections in 
driving the rivets. In the smaller sizes 
the excess is made greater on account 
of the difficulty of making the joint 
tight. If the idea of equal strength was 
carried out for these, there would be no 
end of trouble, as the plates would spring 
in the calking. 

To find the strength of plate in the 
lap in per cent, of solid plate take: 
p—d 
ioo = per cent 8 



RIVETED JOINTS. 49 

And to find the strength of the rivets in 
per cent, of solid plate take: 
an 

100 — - = per cent 9 

pt 
Where /=pitch, ^==diameter of hole, 
#=area of hole, n=number of rows, and 
/=thickness of plate. 





to 

H 
g 
O 

P 


j6 


la 




CD 


s 


4) . 

ft* 

c 
175* 


iCiiNiNOiiN.WW 
T-) CO lO 0) H 
0* « <tt W n 


10' 


W 
H 

> 


.2 EC 
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CD VtfCO ^tO CD "^CCO vtfCD NPptO 
^ cdsrH !>\h h rH J^rH £<H <&rf 

lH CO ID r-l CO O !> 

n rl rH _ ,_, H H 


* 




O 


Length 

of 
Rivet. 


r-irHr-iW(NCi<Mcocococo , 'i<^ 


CO 


O 

Ph 
O 
P* 
Ph 


Diameter 

of 

Rivet. 


iH CO lO rH CO 10 


c* 


* 2 S 


VCO XCCO \?»CD NO)n \*C0 NflOCO r-4 
»-t\,H WNf-i r-N,-| u5\,-| C0\,-| li\,-l 

lO £- OS rH CO lO 


H 



5° 



BOILER MAKING. 



a3 
la 

."2 
"o 

c 




05 05 00 00 i> i> 1> I- i> t- l> J> 1> 


CO 
H 


O « 

PU 


t-cow^eooiNtHoaosojoo 

t» £> i> i> i> i> t- i> I> I> CO CO CO 


0* 
rH 


o 

u 
a 

b/o 
c 
w 




■"*ooiocoHoaooj>i~t~t~co 
j>cococococou5iomioiooio 


tH 




OtHNOOOMOiOMNHOO 
COCOCOCO»Otf50iOlOiOtf3iOlQ 


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05 


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05 H CO »0 rH CO 
r-t rt ^ ^ W N 


t- 



Rivets are pointed in three different 
styles : conical, button and countersunk, 
of which the button and the conical 



RIVETING. 5 1 

when snapped are the strongest, from the 
fact that the snap compresses the metal, 
while in the hammered cone the meta L 
is spread 



CONICAL BUTTON COUNTERSUNK 

Cones are easier to get tight at first, 
yet if they should leak, snapped cones 
are just as readily calked as the ham- 
mered. Except for ornamental work, 
the snapped cone is practically as strong 
as the button which must be snapped. 
Cones should be kept pretty high,not less 
than three-quarters of the diameter of the 
E^g. 33 



rivet. If much lower, they will be weak. 
The holes for countersunk rivets 
should be made at an angle of 60 
degrees, but the taper must not go more 
than three-quarters of the way through, 
the sheet, The countersinking tool 



52 BOILER MAKING. 

should have a tit on its point to guide 
it and prevent eccentricity. A counter- 
sunk rivet should never be used where 
it can be done without, as it weakens the 
plate while its own strength is no 
greater. 

Rivets are driven either by power or 
by hand. For tight work, tjie power 
driven are by far the best. Any power 
maybe used, but to make a good job, 
it requires a double die or set ; one to 
hold the plates together and the other 
to set the rivet. There are several 
machines in the market that do this to 
perfection. They have an annular die, 
which is brought up against the plates 
and holds them solidly together, while 
another die, working inside of it, sets the 
rivet. In such a machine, on girth 
seams of cylindrical work, do not start 
on one side and follow directly around, 
as the least slackness of the faying sur- 
faces will be crowded between the last 
few rivets, making a bad spot to calk. 
But rivet across the quarters, keeping 



RIVETING. 53 

the joint well bolted, then take the 
eighths. This will divide up the slack- 
ness, so that it will not be troublesome. 
The rest can then be driven right along. 

In power riveting, the rivet may be 
heated all over, as the head is held in a 
cupped die which prevents its spreading, 
and consequently the body can be upset 
its whole length, filling the hole solidly 
under the head as well as the point. 

For hand riveting the head cannot be 
heated quite as hot as for power work, 
or it will spread too much under the 
holding-on hammer. This hammer 
should weigh about twenty pounds, and 
have a stout oaken or hickory handle 
from six to eight feet long. And, wher- 
ever practical,- the hook, which carries it, 
should be about one-third of this dis- 
tance from the head. This will allow a 
little play to the hammer, so that it will 
give a blow in answer to. that on the 
point of the rivet, thereby aiding in up- 
setting under the head. For places 
where this hammer- cannot be swung, a 



54 BOILER MAKING. 

bar two and a half to three inches 
diameter and eighteen to twenty-four 
long can be used. And for narrow 
space, such as the sides of fire-boxes, 
which cannot be reached otherwise, a 
block of iron on the end of a long bar 
must be used. These last are not good 
for the rivet, especially if the rivet is 
hammered much after losing its heat. 
It becomes crystalized and is liable to 
break. 

While waiting for a rivet, the plates 
should be well hammered together, 
drawing the bolt up tight in the next 
hole. Have no sharp corners on the 
hammers for this purpose, as they are 
apt to mar the plate. 

If the holes in the plates do not 
match fairly, or shut by, do not use a 
drift. A drift always strains the plate, 
even if it does not start a crack. Ream 
them out until they are fair, and put in 
a larger rivet. A few of which should 
always be kept on hand to meet such 
cases. For reaming holes a good tool 



RIVETING. 55 

is shown in figure 36, a being the cutting- 
edge. The section is enlarged to give 
a better idea of its shape. This tool is 
stronger, and will cut faster, cleaner and 



JFig. 36 




easier, than the usual half (oftener less 
than half) round ones. 

When the helper passes the rivet 
through, it should be held by pressing 
lightly against its side, until he has his 
holder in position. Do not strike it 
sideways, or the chances are that the 
point will be lopsided, and if it should 
happen to leak, the only remedy is to 
cut it out. Work lively now, striking 
the rivet square on the end until it be- 
gins to spread over the plate. Then, as 
fast as may be, shape the point. It 
should always be borne in mind that for 
good work it is just as important to fill 
the hole up solidly as to make a neat 



56 BOILER MAKING. 

point, and this cannot be done without 
quick and hard upsetting. 

For snap work, the upsetting is done 
in the same manner as for hammered 
points. But instead of hammering over 
as the rivet begins to spread, set the snap 
over it and with good swinging blows 
drive it up until the snap just touches 
the plate. The hammer for this work 
should be at least twice as heavy as the 
snap If no heavier, the snap itself will 
absorb so much of the blow that its 
effect on the rivet will be very feeble. 
The lip of the snap should be slightly 
rounded, for, if sharp, it is liable to cut 

Fig. 37 




a a 

the plate, thereby further weakening it in 

its weakest part. See a a in figure 37. 

If the rivet holes are drilled with the 

plates together, the plates should be 



RIVETING. 57 

taken apart and the burrs taken off 
before riveting up. The holes should 
be slightly countersunk on the outside 
as well. 

The shop should never be allowed to 
get too cold in winter, for the sake of 
the work as well as for the sake of the 
men. Because, if the plates get too 
cold and the rivets are driven as well as 
they should be, when the boiler begins 
to warm up quite a number of rivet 
heads fly off. They often break at the 
fay, giving no end of trouble. Others 
still will simply crack partly through. 
Of course the users of the boiler blame 
the maker; the maker, the manufacturer 
of the rivets ; and the manufacturer of 
course retorts that the rivets were 
burned in the heating. Yet all the 
while the trouble was that the boiler 
was too cold. Sometimes the heads 
• drop off before the boiler is warmed up. 
This seldom occurs, however, except it* 
case of very heavy plates or an ext/a 
number of plates are brought togethev. 



V. 

BRACING AND STAYING. 

All shapes not complete circles must 
be thoroughly braced or stayed. This 
includes all elliptic and partially circular 
forms as well as flat. 

The term "brace " is applied to long 
rods reaching across the boiler, while 
"stay" is applied to short bolts and 
other devices in corners or on one side 
only. 

The first and most important point is 
to have a sufficient amount in number 
and size, and if the plate is flat or nearly 
so, they should support it entirely with- 
out regard to the plate's own stiffness. 
The second is, to have them so disposed 
as to present the least obstruction to a 
free inspection. And last but by no 
means to be lost sight of, to allow a free 
circulation of the water. 



BRACING AND STAYING. 59 

Wherever possible, braces and stays 
should draw at right angles to the plate 
that they are intended to support. If 
this cannot be done with a direct brace 
and without interfering with the accessi- 
bility, a modification of the brace or a 
stiffening bar braced at another point 
should be used. It should never be 
necessary to remove a brace to reach 
any portion of the interior. If a brace 
is removed from any cause, the chances 
are equal that it will not be replaced. 

Braces should be fitted to their places 
tight enough to prevent shaking, and 
each brace should draw just as much as 
and no more than its neighbor. Care 
should be taken not to overload a brace 
by straining it in, as it has quite enough 
labor to perform in service. 

Too much care cannot be taken in 
fitting stays and braces. Being out of 
sight and for considerable periods of 
time, especially in case of new boilers, 
there is no way of determining their 
efficiency, save by the failure of the 



60 BOILER MAKING. 

boiler, which generally occurs at some 
critical time. 

The simplest form of stay is a plain 
rod threaded its whole length, screwed 
through two opposite plates, and having 




its ends riveted over; figure 38. It is only 
used in narrow water spaces and should 
be arranged in vertical and horizontal 
rows so that bars and scrapers may be 
more readily passed between them. 
The thread should be fine enough to 
have not less than three full turns in 
the plate. Four is better. The usual 
practice in locomotive fire-boxes is 
twelve per inch, the bolt being %" 
diameter. Now with a tensile strength 
of 50,000 pounds per square inch this 
bolt will support 50,000 times the area 
in square inches at the base of the 
thread, or 50,000 X. 7765' X. 7854 Q „ 
6 = 3845 



BRACING AND STAYING. 6 1 

pounds, using 6 for the factor of safety. 
.7765 is the diameter at the base, the 
thread being of the Franklin Institute 
Standard. To find the distance apart, 
divide the 3845 by the working pressure 
required, say 140, and extract the square 1 
root. Then 3845 -=-140= 2 7.46 (the total 
area the bolt can support) and ^27.46 
=5.24. Another element to consider 
in this connection is that of corrosion, 
and although the bolt may be amply 
strong when new, it is better to err up- 
on the strong side. On this account as 
well as faults of workmanship, which it 
is impossible to entirely avoid, it is 
customary to place them not over 4^" 
apart. 

The distance apart of the bolts allow- 
able from the thickness of the plates, 
can be found from the following 
formula: 

2t 

p = 10 



62 BOILER MAKING. 

In which p= the pitch in inches. 

t= thickness of plate in inches. 

JP=z pressure per square inch. 

X= factor of safety =6. 

<r= tensile strength of plate = 

60,000 pounds. 

Assuming / to be 5-16" which is the 

usual thickness of locomotive fire-boxes, 

we have (.3125 x 2)-+-{Vi4oX6\=5- 2 % 

60,000 
or about the same that the bolt will 
support. The same trouble from cor- 
rosion occurs with the plate, coupled 
with the wear from the fire. They 
rapidly thin down the plate so that 4%" 
pitch is none too close. 

This style of bolt should be fitted very 
tightly especially in a steel fire-box. It 
requires as great a force to screw it in 
as it ^requires to tap the holes. The 
tap for this purpose is best made with 
the reaming portion long enough to 
run clear through both plates before the 
thread begins to cut. The thread, one- 
half of which may be a half-thread deep, 



BRACING AND STAYING. 63 

should be long enough to reach the 
same distance. The shank also should 
be as long, so that the tool may be sent 
clear through and not have to be backed 
out. Backing out is apt to strip the 
thread in steel plate. The appearance 

Fig. 3D 



of such a tap will be as in figure 39 
which is drawn from one of three, which 
together tapped over fifteen thousand 
holes through y 2 " and ffi plates with 
3 y 2 " to ^y 2 " space bet ween, and no one 
of the bolts have failed from faulty tap- 
ping after nearly three years continuous 
service. The diameter of the reamer 
part should be neither more nor less 
than the diameter of the bottom of the 
threap If larger, there will be a pin- 
hole leak, and if smaller, the tap will 
almost invariably strip the thread, if the 
• plate is steel. Too much importance 
cannot be given to these two points, as 
well as to fitting the bolts tightly in the 
thread. 



64 BOILER MAKING. 

Where facilities for cutting off the 
proper lengths of these bolts from long 
rods, cut in a bolt machine, the very- 
handy socket wrench shown in figure 40 



can be used for setting them, the hole 
being tapped the depth required for 
the projection of the bolt for riveting. 

The wrench for screwing in these 
bolts should be double handled, from 
3c/ to 36" l° n g> with the ends turned 
up 4". There should also be several 
single handled ones, on hand for use in 
concave parts such as where the straight 
part of a locomotive fire-box swells out 
to the barrel. 

A projection of one-half the diameter « 
of the bolt should be allowed on each 
end for riveting. Upset square on the 
ends and snap with a shallow tool, the 
object being not so much to cover the 
plate as to fill the hole solidly. Ham- 
mering down the edges has the effect of 



BRACING AND STAYING. 65 

breaking the thread in the plate and in 
the direction of the strain as well. 

Several of the upper rows of these 
bolts are frequently made hollow, with 
the inside end plugged. Or they may 
be drilled in their outer 'ends only. In 
such cases it is advisable to have them, 
yi" at least, larger in diameter to make 
up for the loss of strength. The hole 
may then be of any diameter up to 3-16" 
diameter. The steam blowing through 
the hole serves to notify that the bolt is 
broken. This would not be likely to 
happen if the fire-box was properly stayed 
at the top. 

In locomotive boilers with straight 
top and arched crown sheet as in figure 

F4g, 43 




66 



BOILER MAKING. 



41 this bolt is used with a modification, 
figure 42. One end is enlarged yi a in 

Fig.. 41 




diameter to allow the greater part of the 
bolt to pass through without screwing. 
This necessitates a tap like figure 43 

ICig. 43 




The dimensions x to be long enough to 
take the longest distance over the plates 
and y the shortest distance between 
them. 



BRACING AND STAYING. 67 

Figure 44 is another type of bolt for 





the same purpose. This requires a cop- 
per washer, which should be not less 
than yi" thick, under head and nut. 
Where this bolt is used at an angle to 
the plates the head and nut must be 
faced off to a cone shape, and the copper 
washer made to fit, as in figure 45.' Fig- 
ure 44 is frequently used in locomotive 
boilers for staying the heads, running 
from end to end, and under the crown 
bar. In this case the bolt is not screwed 
into the front head, but has a nut and 
copper washer on the inside as well as 
outside. It is essential to have a sup- 
port for these bolts about midlength, 



68 BOILER MAKING. 

which maybe a plain bar, of 4"X i" iron, 
with holes, through which the bolts run, 
and having its ends turned at right 
angles for riveting to the boiler shell. 
Without this support the continual surg- 
ing of the rods, when in service, would 
soon loosen them and set at defiance all 
attempts to make them tight. Properly- 
fitted there is no better stay for that 
portion of the back head opposite and a 
little above the crown sheet. A tee or 
angle iron with a diagonal brace is diffi- 
cult to get in, the space being so 
limited. In some cases this place has 
been supported (?) by a bolt like figure 
i, screwed into the crown bar, an ar- 
rangement that can not be too heartily 
condemned. The duty of a crown bar 
is severe enough without subjecting it 
to any other than # its legitimate strains. 

Various styles of bolts are used for 
fastening the crown bars to the sheet, 
including a plain rivet with head above; 
a common bolt with end tapped through 
and riveted over the sheet ; the same 



BRACING AND STAYING. 69 

tapped through the sheet but nutted on 
the fire side. Figure 44 is also used. 
A nut should never be used in the fire, 
as it is liable to fail at any moment. 
Nor is it advisable to tap through the 
crown sheet. In case of leakage or 
failure of any kind, the bolt will require 
replacing and the hole must needs be 
retapped a little larger. It frequently 
happens, as well, that the water contains 
such impurites that it necessitates the 
entire removal of the crown bars for 
cleaning. It will readily be seen what 
trouble and expense arises from riveting 
or screwing into the sheet. The best 
style of bolt used at present is shown 
with its washer in figure 46. This bolt 
is now kept in stock by several bolt 
manufacturers. The difference in cost 
over a plain bolt is more than offset by 
the saving in tapping. A bolt of this 
kind is tapered under the head for about 
an inch of its length, increasing its dia- 
meter 1-16" ; so that if the hole in the 
plate is 1-3 2" larger than the body of 



7 o 



BOILER MAKING. 



the bolt this tapering portion may be 
driven in solidly. The chips or shaving 
caused by the driving fall into the little 
groove under the head, and therefore 
do not require the withdrawal of the 
bolt for clearing out, so that if once 
driven solidly it remains there. The 

Kig-46 Fig^ 427 




r 



»i tj n g ifwn 



rule for spacing crown bar bolts is the 



BRACING AND STAYING. 7 1 

same as for ordinary stay-bolts. This 
also determines the distance the bars 
will be from centre to centre. The style 
of crown bar most frequently used in 
this country is shown in section in fig- 
ure 47, and in side elevation in figure 
48. The thimbles a and the toes b are of 
cast-iron, but often the thimbles are of 
wrought iron — a needless expense — and 
the bars are welded together at the ends 

Fig. so 




s 



and drawn down to form the toes, as 
in figures 49 and 50. The welded toe 
has the very desirable abvantage of cov- 
ering less of the plate than the cast-iron 
ones. It also allows a better circulation 
of the water. The toes should be closely 



72 BOILER MAKING. 

fitted to the edge of the side plate and 
the turn of flange of the crown sheet. 
Be careful to have them long enough so 
that they will not be raised from their 
bearings when the thimbles are in place. 
The tap should be caulked (on the out- 
side only) before the bars are fitted. 
The thimbles should be tapering so that 
while giving a bearing the full width of 
the bar they will present as small a sur- 
face to the bar as possible. With a 7/% 
bolt and ^" bar, a good proportion will 
be 2.y 2 " outside and i" inside diameter 
at the top, while the bottom may be iffi 
outside and 1}/%" inside diameter. They 
should never be less than 2" high, and if 
long stay rods run beneath them 2*^" is 
none too much. There being such a 
small amount of water above the crown 
sheet — gauge-cocks, etc., being set usu- 
ally to carry but 3" to 9" depth — that 
with the great heat playing underneath, 
the steam forming below the bars has a 
great tendency to blow the water there- 
from with frequently disastrous results. 



BRACING AND STAYING. 73 

The size of these bars may be deter- 
mined from the formula for a beam 
supported at both ends and weight 
equally distributed, though the practice 
for such bars is 4% "X^/i" for crown 
sheets 40" to 48" wide. With the 
above thickness of bar, and disregarding 
the crown sheet which is of very great 
assistance in such a construction, to 
find the height make 
h _VwXkxl 

U — ; II 

ZcXb. 
in which /z=height in inches. 

w=total load in pounds. 
k=i actor of safety=6. 
/=length of span in inches. 
r=tensile strength of bar in 

pounds. 
b=total breadth (thickness) of 
bars in inches. 
With a span of 44* and a pressure of 
140 pounds per square inch and the dis- 
tance centre to centre of bars 4^" we 
find w==44X4^X 140=27,720. Then 
we have (27,720x6x44=7,318,080) — 



74 BOILER MAKING. 

(8X30,oooXi^=36o,ooo)=2o.328, the 
square root of which=/L5, the height 
required. 

In figure 48, dd, are short links to 
which the slings are attached, and in 
this connection it is well to consider the 
enormous force which these slings are 
required' to resist. It is an amount 
equal to the diameter of shell X length 
of fire-box shell X pressure per square 
inch less that amount resisted by the 
back head and throat plate. All of the 
remainder not entirely resisted by the 
slings must needs be thrown upon the 
sriort stay-bolts on the sides. That it is 
not carried by the slings in many cases 
is evidenced by the fact that so many 
fire-boxes are fitted with hollow stay- 
bolts near the top, to give notice of 
their breaking, which is from no other 
reason than lack of slings in number or 
size. To determine just how much 
strain will come upon the slings is diffi- 
cult, if not impossible, buf two slings 
having a sectional area of from itoi^ 



BRACING AND STAYING. 75 

square inches to each alternate bar, are 
not enough. There should be at Jeast 
two slings to every bar, and of nearly, 
if not twice such area. 

The slings are made in three parts ; 
the foot, the brace, and the links. Some- 
times the brace and foot are in one. 
This is objectionable, as it necessitates 
cutting out rivets to allow removal. The 
link d, figure 48, is a flat bar, with a hole 
at each end, just long enough to allow 
the fork of the brace to be made fast to 
it, while the lower pin is in the center 
of the bar. These links are sometimes 
forged to a shape like figure 51. A 



square rod of proper length welded in 
hoop form is flattened down with pins 
to keep the eyes open. This makes a 
very neat job, but it is liable to straight- 
en in service, unless it is welded to- 
gether, which makes it expensive. The 



76 BOILER MAKING. 

foot has a plate through which it is riv- 
eted to the shell. The lug is welded to 
this plate, and this should be done with 
the greatest of care. A good way is to 
mortise the plate, and drive the lug 
through from the back. Figure 52. 
The lug being upset it can be driven in 




solid, and finished off at one heat with 
very little trouble, the finished foot 
appearing like figure 53. Where the 
brace comes into a dome or upon a side 
surface, it is made like either figure 54 
or 55. Where the twist is not too 
short, nor the offset very great, figure 
55 is the best, as it requires no welding. 
Figure 54 is stiff, and if the welding is 
thoroughly done, it is naturally superior. 
But welding in such work can seldom 
be guaranteed. 



BRACING AND STAYING. 



77 




The brace itself may be made of a 
rod with jaws on both ends like figure 
56. For such short braces as crown 



slings, two flat bars slightly riveted to- 
gether, with washers between them, are 
much to be preferred, as they are not 
welded, and can so readily be marked 
off in their places. Take one of the bars 
and drill one end. Then set up with 
pin in place, upper end is best, hold the 
other end against the link, and scribe 
through the hole. This bar can theif 
be laid upon the other, and used as a 



78 BOILER MAKING. 

jig to drill it by. Figure 57 shows a 
brace of this description, which com- 
mends itself for its cheapness, as well 
as for its reliability. 

Fig. 5V 



Fig. 58 



The pins for jointing braces should 
be parallel, and never be split to retain 
them in place. A nut gives great 
' trouble in removing. After a short time 
only it may necessitate chipping off. 
This can be avoided by using a split 
cotter. Figure 58 is a pin that gives 
good satisfaction, and can be made en- 
tirely by machinery. Parallel in body, 
with point tapered so as to be entered 
easily, the cotter preventing its working 
out, it does not bind the parts together, 
so that if the brace does not draw, it is 



BRACING AND STAYING. 79 

easily detected. This cannot be done 
with a nutted bolt. 

With the crown bar we have just been 
considering, using two slings, we have 
27,720-^2=13,860 pounds,for each sling 
to carry. Then with a tensile strength 
of 30,000 pounds per square inch of 
section, we must have 13,860-^-30,000= 
.462 of a square inch without allowance 
for a safety factor which would make 
it .462X6=2.772 or over 2^ square 
inches. This, considering the support 
given by the end plates of the fire-box, 
may be excessive, and a factor of 4 may 
safely be used, making it .462X4=1.848, 
or about ij4 square inches. If better 
iron than refined is used, then their 
size maybe reduced in proportion, sub- 
stituting the tensile strength for the 
30,000 in the calculation. It may be 
well to note that not a few boilers are 
now in use, having but two slings to 
each alternate bar, and the section in 
the slings but little over 1^ square 
inches. All are more or less troubled 



So 



BOILER MAKING. 



with leaky and broken stay-bolts. The 
only thing that saves the boiler from 
destruction is the heavy leg frame and 
the heads, and not the inherent strength 
of the construction. 

Figure 59 is a plain crowfoot brace, 

Fig. 59 




which is very handy and good where a 
short stay is desired. Do not be afraid 
to put large rivets in the feet, as some 
boiler-makers appear to be, often using 
two y%" rivets to hold a rod i}i" diam- . 
eter. A comparison of the areas will at 
once show that the rivets are too small. 




For long braces, tee and angle iron is 
used for feet, with an eye on the rod to 
fit over or between as in figures 60 and 



BRACING AND STAYING. 8l 

6 1, The angle iron in figure 61, is ob- 
jectionable for its tendency to straighten, 
and "thereby acting as a powerful lever 
to pry the heads of the rivets. 

Figure 60 is good as long as the 
surface to which it is riveted is flat, 
but if it is curved, it is dangerous 
from the fact that rolled tee iron is 
never solid at the root of the stem. 
This will show for itself very plainly if 
an attempt is made to bend it, hot or 
cold. The best way to make a tee is to 
flange it up from a flat piece of Ex. 
Flange iron or of steel, to a section 
shown in figure 62. This tee iron can 

n Eig.63 



3) 



be curved readily both ways, and is the 
only thing that should be used at the 
sides of locomotive "wagon top" boiler 
just forward of the fire-box. The meth- 
od of forming this tee will be given 
under the head of smithing. 



82 BOILER MAKING. 

A few rivets through the stem of 
the tee close down to the corner will 
enhance the stiffness to such an extent 
that there will be but very little dif- 
ference, if any, between it and a solid 
rolled bar. In placing such rivets be 
careful to keep them away from the 
spaces required for the jaws of the 
braces. 

It may be, where the shape of the 
boiler is particularly crooked, an ad- 
vantage to make the tee of two pieces 
of angle-iron, so as to fit separately. 
In such a case they must be riv- 
eted together after fitting. Drill or 
punch the holes in one, and lay to- 
gether in their places, and mark the 
other from it. After riveting to- 
gether, try it in and refit, as there may 
be a little alteration in shape caused 
by the "drawing" of the rivets. 

Lugs for single braces can be made 
up in a similar shape, but as they 
would be narrow they should be 
welded in the stem. 



BRACING AND STAYING. 83 

Lay out the rivets for such tee irons 
by the same rule as used for stay-bolts 
on the sides of fire-boxes. That is, with 
due regard to the diameter of rivets 
used. 

Simply stiffening a surface with tee 
or angle iron without bracing from an 
opposite point, should not, under any 
consideration, be allowed. The effect 
of so doing is to throw such weaving 
ing strains upon the plate at the turn of 
the flanges, as to soon crack them 
through. Two boilers that were built 
or repaired (?) by a prominent railroad 
corporation, and whose mechanical en- 
gineers are held up for patterns of ex- 
pertness, came receritly under the au- 
thor's observation. The back heads had 
to be replaced by new ones. Both were 
badly cracked on each side, a a figure 
63. Patches had been applied on both 
sides of one, and one side of the other, 
and two of the patches even were 
cracked. The tee was made of two 
6^"X4"X^" angle iron, the long 



84 



BOILER MAKING. 
Fig. 63 




legs riveted together, and reaching as 
close to the sides as the curve of the 
flange would permit. Good enough in 
itself, but being so stiff that it concen- 
trated all the spring upon the • flange. 
Yet had it been reinforced by a few 
stay rods, to some opposite part, there 
would have been no trouble whatever. 



Fig. 64 




In laying out for tee iron brace feet, 
be careful to so dispose them in such 
directions that the fork of the rod does 
not meet them at a transverse angle, as 
in figure 64. The evil effects can be 



BRACING AND STAYING. 85 

seen at once from the figure. They 
may be swung around the axis of the 
pin without any bad resuts, how- 
ever. 

The opposite ends of these braces may 
be made fast to feet like figures 55 and 
56. On account of removal, these feet 
should never be forged on the rod, al- 
though it is frequently done. 

In large boilers to reduce the number 
of rods, recourse is frequently had to 
such devices as are shown in figures 65 
and 66,. care being taken to make the 
rods larger to correspond. 




86 



BOILER MAKING. 
Fig. 66 




Figure 67 is a modification, often 

Fig. 67 




used, of figure 65, and it is claimed to 
be cheaper. It saves drilling one hole, 
but it would seem to be much more 
troublesome to hang on account of the 
dropping of the ends. To set these 
heavy braces requires heavy turn- 
buckles. An example of this is given 
in figure 68. 



BRACING AND STAYING. 87 

Fig. 68 




Throat or belly stays in locomotive 
boilers, from their being exposed to the 
sharpest current of flame or hot gases, 
must be thoroughly made and should 
cover as little as possible of the surface 
of the plate that they support. 

Figure 69 is largely used for this pur- 



^ 



Fig. 70 



pose being a simple crowfoot brace with 
the stem made of flat bar. Usually of 
2" X W stock. The foot 7" long with tne 
rivets 43^ " centers. Being riveted to the 
throat sheet it is necessary to offset the 
stem to pass over the rivets of the lap. 
Some master mechanics reject this stay 
as covering too much surface, and use a 
brace like figure 70, which has a decid- 



88 BOILER MAKING. 

ed advantage in this respect/but requires 
twice the number to support the 
same surface. It is made of 2"x]/^ rr 
iron with a lug forged on the end in 
which to screw a plain stay-bolt. The 
end of this stay is kept clear of the tube 
plate at least ffi '. An inch would be 
better. The stay-bolt screws through 
the sheet as well as the lug and is rivet- 
ed over upon the inside of the fire-box. 
Gusset stays are those made of plate 
iron and fastened to the boiler by angle 
iron, as per figure 71. They are prop- 
Fig. -71 




erly set radially to the boiler so that 
the angle iron fastening, them, to the 
shell will then require the least amount 



BRACING AND STAYING. 89 

of smithing. The objection usually 
given to these stays is that the greatest 
amount or strain is thrown immediately 
upon the edge of the plate, and on this 
account most engineers refuse them. 
This is something of a mistake, as trie 
greatest strain does not come upon the 
edge, but upon a line drawn through the 
centre of the outside rivets, a a, in the 
figure. It is evident, then, that the 
width from the edge to a line {b b) 
drawn in the centre between the first 
and second rivets will be the amount to 
resist the strain. In a stay in actual use 
this width was 3^2" and the plate yi" 
thick, making a sectional area of 3^ X 
|4 = 1,3125, equivalent to a round 
rod over 1 ^ " diameter, surely sufficient 
to support any surface that the rivets 
would hold, without counting the sup- 
port given by the remainder of the plate. 
A great advantage of such stays over 
long rod braces, is their leaving so much 
space for working in. 

Figures 72, 73 and 74 are familiar 



90 BOILER MAKING. 

types as used in marine boilers. Figure 
72 is bad in that it covers too much of 
the surface of a heated plate, and 
that it depends entirely upon its own 
stiffness to resist the strains. Figure 73 
is much better, yet the crowfeet cover 
too much surface. Figure 74 is the 



ITigiVS • 




BRACING AND STAYING. 


IP-'ig;:. 744 


Mta^g) 


r 








oAo\ 





\^ 6 \ 







\°- 



91 



best of the three, being stiff, strong, and 
presenting the least amount of surface 
to the plate. Never use a brace or stay 
that is bent over to form a foot on one 
side only. Being liable to straighten 
out, no reliance whatever can be placed 
upon them. 



VI. 

FLANGING. 

Bending down the edge of a plate to 
form a flange, without injuring it, at the 
same time leaving its surface smooth, is 
a piece of work requiring skill, quick- 
ness and sound judgment. A flange 
should never be turned of less inside 
radius than the thickness of the plate ; 
nor greater than sufficient to allow the 
same distance from inside to centre of 
rivet line, as from centre to centre of 
stay-bolts required to support the flat 
portion of the same plate. Up to this 
limit, the greater the radius the better, 
as the fibres of the metal are not so 
severely strained nor is the plate so 
much reduced in thickness. 

There are two general methods of 
flanging. One with a "former" large 
enough to shape the whole plate over ; 
the other with but a small iron block 



FLANGING. g$ 

or anvil. Sometimes even a block of 
wood is used. For thoroughly satisfac- 
tory work the first plan only can be 
used. And only lack of time or other 
compelling cause should allow of any 
other method. The cost of casting the 
full former is practically nothing as 
compared to the cost of time and fuel 
saved. The iron is always good stock, 
and can be broken up and remelted if 
it is not thought desirable to save. 

The former should be heavy, say i}4 
thick, with a flange around it of the 
same depth as the flange desired on the 
plate. The pattern should be made 
with a standard rule, no allowance what- 
ever being made for shrinkage. In such 
castings the shrinkage is but very trifling, 
and the flange, no matter how closely it 
is driven down, will always spring off 
sufficiently to make up for what little 
occurs. 

The opening for the female flange of 
firedoors on the same account should be 
made larger than the standard rule will 



94 BOILER MAKING. 

give it. Not less than 3-16" per foot, 
while that for the male flange should ba 
from the standard. This to allow some 
freedom when setting up. When to- 
gether, the male flange is heated and 
expanded with mauls to fit. The flanges 
of the former should be thick enough to 
allow one jaw of a clamp to be set on 
the edge of it, while the opposite jaw is 
resting on the flat of the plate, and clear 
of the turn. If the turn is of large 
radius there may, to save weight, be a 
supplementary flange or rib, parallel to 
the outside flange and inward a sufficient 
distance for the purpose. Figure 75 
shows a section of former with plate 
clamped upon it. 

IFig- 75- 




Having a former of the full size and 



FLANGING. 95 

proper shape, no laying out is necessary 
until after the plate is flanged, except 
to locate a couple of holes for the 
steady pins, which hold the plate in 
position while working the flange. 
These holes should be made of suitable 
size for closing with rivets. Be careful 
to place them so that they will not in- 
terfere with the stay-bolts. Corres- 
ponding holes are required in the for- 
mer. The pin should be somewhat 
tapering, so that it can be driven in 
tightly. It is easily loosened by rap- 
ping the plate close beside it. 

The former, especially about the turn 
of the flange, should be examined for 
roughnesses and irregularities, and all 
carefully smoothed off. 

The fire for flanging should be long 
and narrow, the idea being to heat as 
long a section of the plate as possible, 
without going far back from the line of 
turn. Making the tuyere of a pipe 
with a row of holes longitudinally, will 
enable this to be done. If much circu- 



96 BOILER MAKING. 

lar or curved work is to be done it will 
pay to have a curved tuyere. 

Have a good coke fire and bank 
thoroughly with wet coal or fire brick. 
After laying the plate on, bank care- 
fully all around it so as to confine the 
heat to the plate and not waste it and 
time by blowing it away. Bring up the 
heat slowly, especially for steel. For 
iron a good bright heat is wanted, but 
for steel a light cherry red is as much 
as it will stand. 

Lose no time between the fire and 
the former, for the plate rapidly loses its 
heat, and it should never be necessary 
to heat twice for the same section. 
Three bail hooks hung from a scale 
beam lever, a " monkey tail " at the 
opposite end, the whole carried on an 
overhead traveller, is a very handy de- 
vice for carrying the plate back and 
forth. See figure 76. 

The forge should be low ; not over 
18" from the floor. The former should 
be blocked up about a foot high, to 



FLANGING. 97 

allow freedom for entering the clamps. 

When the heat is right, get your 

hooks ' under the edge of the plate 

IF±g_ 76. 




before you clear off the top. While 
doing this reduce the blast, but do not 
shut it off entirely until the plate leaves 



98 BOILER MAKING. 

the fire. In other words, keep the heat 
in the plate as long as possible, at the 
same time working over the fire without 
being choked with the gases. Have a 
broom ready to sweep off the cinder, 
and dust as soon as the plate is lifted 
off. Do not be afraid to stoop' and see 
that the under side is perfectly clean. If 
there are hard lumps burnt on, so that 
the broom will not move them, use a 
chisel-pointed bar to cut them off. 
Keep the former well swept also. 

If all is clean, drop the steady-pins 
into the plate and swing it over the 
block, gently lowering it while fishing 
with the pins for the holes in the block. 
Jt is much easier to find the holes with 
the points of the pins while the plate is 
suspended, than if it were down so that it 
could not be seen under. As soon as the 
pins have entered, let go with the hooks 
and run them out of the way. Drive 
the pins in solidly, and set several clamps 
along the edges away from the heat. 
One to be close to each end of the heat. 



FLANGING. 99 

To handle plates about or steady 
them while hanging, a porter hook is a 
deal more pleasant and effective than 
leather mittens. There should be a 
straight and a right angled one for 
every man at work about the flange fire. 
The mouth should be about 4" deep 
and wide enough to take the thickest 
plate used. Jaws 1" thick and 1%" 
wide at widest part. Handle about 1" 
in diameter and 24" to 30" long. Figures 
77 and 78 show the two kinds and 
the method of using. 

IF±g- 77. 



c 



(See fig. 75, page 94), 
:F±g. 78. 



Figure 78 can be used either 



IOO BOILER MAKING. 

side up with equal facility. These 
hooks are handy anywhere in the 
boiler' shop for either plate or angle 
iron. In carrying materials with them 
the men can face the direction in which 
they are walking, thereby making better 
progress, and with less danger of stumb- 
ling. 

As soon as the plate is secured to the 
former, beat down as fast as possible 
with found faced mauls, striking at first 
about the middle of the overhang. If 
struck too near the edge the plate will 
buckle up, and if too near the flat the 
edge will turn up. As soon as the turn 
is started from the flat, weight it down 
with heavy blocks of iron. This pre- 
vents the flat of the plate from lifting, 
and will save considerable work in flat- 
tening down afterward. 

The mauls for this purpose should be 
of hard wood. Hornbeam is the best 
as it requires no banding as hickory 
or oak do. They should be 5* or 6" 
diameter, 10" or 12" long with hemi- 



FLANGING. • IOI 

spherical ends. The helves should be. 
the same as are used in sledges. 

When the turn is down, take a large 
faced flatter, and flat off the straight 
part of the flange. Use a small sledge 
for this or the flatter will make its mark. 
Flatters should be provided with iron 
handles as wooden ones are burnt very 
quickly. They should encompass the 
tool and not run through an eye. See 
figure 79. The faces of such flatters 
IF±g- 79. 




jF±g. SOi 




should be about 3" square, and have the 



102 "BOILER MAKING. 

edge rounded off all around, commenc- 
ing about s/%" from the edge, and turn- 
ing up about }i", as shown in section in 
figure 80. . 

If by this time the plate has not 
grown too cold, throw off the weights 
on the flat and if it buckles up, set it 
down with a flatter, while a helper holds 
a large sledge or block of iron against 
the flange. But if the plate does not 
show a redness, put it back on the fire 
and reheat. Never strike it while it is 
black, or the effect will be that of 
"piening," which will be relieved as 
soon as heated and the plate will be as 
bad as ever.' 

While one heat is being worked offy 
have a man at the forge cleaning and 
rebuilding the fire so that it will be 
ready the moment the previous heat is 
done. A good flange turner will never 
let the heat out of his plate, when once 
started, until it is ready for the anneal- 
ing furnace or layer out. 

In place of weights to prevent buck- 



FLANGING. 103 

ling while flanging, some use wooden 
staves, 21/2," to 3" square, sprung in be- 
tween the plate and the overhead tim- 
bers, The length of such staves being 
just the distance from the timbers to 
the top of the former, the thickness of 
the plate allows the necessary amount 
of spring required to give the pressure. 
It is hardly necessary to remark, that if 
the shop is high, and high it should be, 
that these staves would be impractical 
as they would be too long and un- 
weildy. 

To flange over an anvil, small block 
of iron or piece of timber, the plate 
must have a line drawn all around it 
just where the turn of the flange begins 
to leave the flat. As a a in figure 81. 
IF±g_ 81. 

* \ "*-•-._ -.--fe 



This line is a guide for a gauge, for which 
a large steel square may be used. A 



104 BOILER MAKING. 

point being marked on its inner edges, 
each way, from the corner a distance 
equal to the outer radius. Figure 82 
shows the method of marking and ap- 
plying the gauge to the work. The 
mark, c, must follow the line of prick 
IFig. 82, 



^^^^ 



1 



punch marks at a a, figure 81, while 
mark d indicates where the straight part 
of the flange begins. 

It will be seen very clearly from fig- 
ure 82 how much trouble and inconve- 
nience will arise in working after this 
plan, yet a great many neat pieces of 
flanging have been done with it. The 
greatest care must be taken not to drive 
the flange too far, or it will necessitate 
turning over to drive it back. 

Figure 83 is a throat plate of a loco- 
motive boiler, and should be from 10 to 



FLANGING. I05 

15 per cent., or the next sixteenth of an 
inch thicker than the rest of the shell, 
on account of the drawing of the metal 
in the concave flange. In an ordinary 
IFig- 83. 




sized boiler with a flange 2" inside ra- 
dius and 4" straight (for double riveted 
seam), * the ' edge will be drawn in 
thickness as much as 1-16". For the 
same reason, extra allowance must be 
made in the height of the rough plate, 
5" is usually sufficient. " The corners, c 
c t having no resistance on one side, do 
not stretch • as the middle portion 
does, and in consequence are pulled in. 
Before trimming, the wings will appear 



106 BOILER MAKING. 

as in the dotted lines. This concave 
flange requires a special former. The 
side flanges may usually be turned on 
the former for the back head. Turn 
the concave first as there will be a better 
chance to hold the plate upon the for- 
mer. 

Figure 84 is a difficult piece of work, 




used to connect a " Belpair " fire-box 
to the barrel. Two formers were used 
for this ; one for the hole, the other for 
the back side. The hole was flanged 
first. The former for the back had four 
lugs or brackets, cast upon its face, 



FLANGING. I07 

high enough to take full hold of the cir- 
cular flange. These brackets served to 
steady the plate while the back flange 
was turned. Extra allowance of stock 
was necessary on the top and sides as 
those portions were drawn- in by the 
flanging of the hole. 

Domes should be riveted up before 
flanging except that portion of the lap" 
that comes in the flange, which must 
not be punched until afterwards. Make 
extra allowance of stock on the corners 
for drawing. A line of points should 
be made on the inside, similar to those 
in figure 81, as a guide. The barrel 
plate should be rolled up to shape and 
used as a former to fit the dome by. 
After the dome flange is fitted, it can 
be used in turn as a former for the 
barrel plate. 



I08 BOILER MAKING. 



VII. 

WELDING PLATES. 

To weld plates the greatest care should 
be taken to prepare the surfaces, as 
well as to get the proper heat. A per- 
fect weld is flawless, the two parts being 
united equally throughout the length of 
contact, and they must be brought to- 
gether before they will unite. All scale 
and cinder must be expelled. Scale, 
in the presence of a flux, and cinder, 
while hot, are fluid, and it is obvious 
that if the surfaces are concave or have 
concave spots, that when they are 
brought together, the sides of the cavi- 
ties will unite and imprison them before 
there is a chance for them to escape, 
and no matter how hard the metal is 
hammered or pressed together a flaw is 



WELDING PLATES. - 109 

inevitable. Figure 85 shows a method 
Fxg. 85. 

of preparing plates for welding .given in I 
an English work on boiling-making, it 
appears as if intended to catch all the 
cinder and scale possible. It is de- 
scribed as follows : " Thicken both 
edges, and split one and taper the other 
as shown in Fig. , which is a section 
or edge view. When this is done, force 
one into the other, and close them over. 
* * * * Then secure the two ■ plates 
by two or three pieces of angle iron 
bolted to them, also two stretching 
screws, and then place on the fire. 
When the plate is hot, the expansion of 
the metal acting against the stretch- 
ing screws, will weld the plates even be- 
fore they are hammered on the block, 
which of course must be done when suf- 
ficiently heated." 
All of which is correct as far as it 



IIO BOILER MAKING. 

goes, but if this splitting and tapering 
is done by hot chisel, hammer and 
swedge, there will be a greater. or lesser 
number of little pockets to hold the cin- 
der and scale. The very hammering 
down of the edge before placing on the 
fire will serve to confine the old scale 
formed in preparing the joint. Unless 
the joint were made a perfect fit by 
planing, a safe job could not be made ; 
and even then cinder may enter because 
of the jaws of the split plate expanding 
a little before the tapered one expands 
to meet it. 

About the only way to join plates 
with the ordinary tools at command of 
the boilermaker is to make a scarfed 
lap-weld as in figure 86. 
Fig. 86. 

In placing together allow them to 
shut by sufficiently to make a little 
thicker than the original plates. This 



WELDING PTATES. Ill 

to allow for the natural waste of the fire 
and to be certain not to go under thick- 
ness. The appearance of the weld be- 
fore dressing down -in finishing will be 
like figure 87. 

!F±g- 87. 

^ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZL 

It will be noticed, in figure 86, that 
the welding surfaces are convex. This 
allows the middle of the joint to make 
contact first, and by the gradual closing 
from the middle to the edges, it squeezes 
out all scale and cinder that is between. 
It must be born in mind that the edges 
of the joint must be the last part to be 
brought together. 

It would be well before strapping the 
plates together to go over the welding 
surfaces with a coarse file or piece of 
gritstone to clean off all the old scale 
formed during the scarfing. 

To weld the longitudinal seams of 
cylinders, the same kind of scarfed lap 
should be made. The plates being 



112 BOILER MAKING. 

previously punched for the transverse 

riveted joint, to within ten or twelve 

inches of the scarf ; rolled up to shape 

and strapped inside with stout bars. 

The plate coming on the inside of the 

lap, to be rolled to the exact circle while 

the one on the outside must be left 

large after passing the punched section. 

Figure 88 shows the form in which to 

get the ends of the plates, the thickness 

being exaggerated to show it more 

plainly. 

IF±g_ 88. 




To prevent distortion when cold, it is 
best to heat the full length of the joint 
at once, but only hammer down a short 
section at a time, say eight or ten inches, 
and reheat. Commence in the middle 
and work both ways. 



WELDING PLATES. 113 

If the circle is large enough to admit 
of swinging the hammers on the inside, 
a block of iron, of a shape to fit the 
outside when finished, will be needed 
for an anvil. If too small for this, then 
a stout mandrel, or stake with face to 
conform to the inner surface of the ring, 
when finished must be used. 

The writer has seen a cylinder 24"' 
diameter, 36" long and 5-1 6" thick, 
with longitudinal joint welded in this 
manner. Tested under a hydrostatic 
pressure of 1,250 pounds per square 
inch, it did not show the first drop 
through the welded joint. It failed 
from the bursting of a head through a 
stay rod hole! After receiving a new 
head it was subjected to an air pressure 
of 850 pounds per square inch, and after 
three weeks it had leaked down but 7 
pounds. 

It is particularly necessary for weld- 
ing to have a perfectly clean fire. No 
fresh coal, but simply coke should be 
used. The heating must be done gently, 



114 BOILER MAKING. 

so as to give time for it to pass through 
the plate to the welding surface. Iron 
should come from the fire at a white 
heat ; steel at a bright cherry. 

The first blows upon the weld must- 
be very light, and not till the plates are 
united should very heavy blows be 
given. As soon as the union takes 
place finish off as fast as possible with 
flatters. 



VIII. 

ANNEALING. 

All plates, particularly of steel, upon 
which flanging or welding has been 
done, should be annealed. It is not so 
imperative for flanged iron plates, ex- 
cept such as are in contact with the fire, 
but all welded plates should be so 
treated. 

To anneal, get the plate evenly heated 
to- a glowing red. It must then be al- 
lowed to cool slowly, and as evenly as 
heated. Cover it with ashes or some 
material that will prevent cold currents 
of air from striking it. To get the heat 
a special furnace is the best and cheap- 
est, if much work is done. It is speci- 
ally economical where boilers of the 



Il6 BOILER MAKING. 

locomotive type are made. Lacking a 
furnace, support the plate at its corners 
with brick, about a foot above the floor, 
and build a good even fire of. wood or 
charcoal, (charcoal is best) under it. 
The flange must be down. Keep a 
constant watch upon the plate, and if it 
reddens up in spots, quickly shove the 
fire aside that lies directly under them. 
And conversely if the plate reddens up 
generally, leaving dark spots, get hot 
coals under those spots as soon as can 
be. 

Have a bed of dry sand made per- 
fectly smooth and level, for the plate to 
cool off upon. Turn the plate, with 
flange up, upon this bed, and cover as 
quickly as possible with hot sand or 
ashes. Do not drop the sand on in 
shovel-full heaps, but distribute the 
sand, as thrown, over as great a surface 
as possible without stopping to spread it. 

A good arrangement for covering a 
plate while cooling is a box made of 
No. 8 or No. 10 iron, inverted over it. 



ANNEALING. 117 

This will save a great deal of shoveling 
with just as good a result. 

It being impractical to make a furnace 
arge enough to take cylinders, they 
must needs be heated by an open fire. 
Stand it on end, a little above the floor, 
and build a fire inside and out against 
the part that is welded. It will not be 
necessary to go all around it. Cool off 
by allowing the fire to die out, screening 
it from cold drafts of air. Be very 
careful to prevent an abrupt termina- 
tion of the heat. 

The general appearance of an anneal- 
ing furnace is that of the one ordinarily 
' used for reheating ; the difference 
being in the size of door and bed as 
well as in the arrangement of the flues. 
Figures 89 and 90 are respectively 
a longitudinal section and cross section 
through the flues. The door being so 
long is made in two parts. One would 
be cumbersome and difficult to manage 
from its liability to warping from the 
heat. The flues are so arranged that 



n8 



BOILER MAKING. 



HHHt iHHHHHHjHH 




ANNEALING. 119 

by the use of the dampers the play of 
the fire upon the plate can be readily 
controlled. A peep hole being pro- 
vided in the door, one is enabled to 
watch the plate, and if one portion 
seems to be receiving more heat than 
:F±g_ 90. 




another, the damper in the flue opposite 
is closed, compelling the heat to go 



120 BOILER MAKING. 

through another flue and thereby caus- 
ing it to pass over the less heated por- 
tion of the plate. 

In the furnace from which the cuts are 
taken the door opening is 5' 6" wide. 
The inside being 7' o" by 8' o. The 
grate is 8' long by 2' 9" wide. The 
bridge wall 2' 6" above the grate and 
18" above the bed. From top of bridge 
to roof at centre 9", and at sides 3". 
The bed is of sand and 2' 3' above 
the floor. The flues are about i6yi" 
wide and 10" high. 



IX. 

SMITHING. 

It being impossible, in a work of 
this kind, to give a description of the 
methods of forging all the multifari- 
ous details that are used in boilers, 
a few of the principal ones only are 
given, as hints of what can be done 
by a little outlay to save a deal of 
hard work and a much greater ex- 
pense, at the same time making a 
more uniform product, thereby sav- 
ing a further expense in chipping and 
fitting. 

Where two laps intersect, the cor- 
ner of the plate that comes between 
must be drawn out to a taper to pre- 
vent an abrupt offsetting of its mate. 



BOILER MAKING. 



Never use a "dutchman" instead of 
tapering. It will be a trouble from 
the first — not only to keep it in place 
while riveting, but. to get tight when 
calking. The plate should be all 
trimmed and punched except the cor- 
ner to be - thinned. The holes in this 
portion must not be punched before 
setting up, but drilled and reamed" 



F.ig. 92 



Fig. 91 

4 1 



when in place. The tapering should 
take in the full width of lap and be 
drawn to as -thin an edge as possible. 
The corner of the plate is shown in 
figure 91, and a section of the joint in 
figure 92. 

Keep the plate level on the anvil, 
and after drawing, dress it down with 
a flatter. If it is very rough or of an 



SMITHING. • I23 

uneven surface it will be almost im- 
possible to prevent leakage. Allow 
it to spread a little on the edge a. 
This edge should not be trimmed 
until the plate is riveted into its place 
and ready for calking. 

Curved crown bars, are awkward 
and expensive forgings to work up 
without " formers ;" especially so if 

Fig. 93 





the ends are welded together. Take 
for example the bar shown in figure 
93. It is well to have two formers for 
such, one for the ends and one for 
the general shape. It will be under- 
stood that this bar is formed in two 
parts and welded together at the 
ends after shaping them. The ends 
of the bars are trimmed roughly to 



124 



BOILER MAKING. 



the shape in figure 94, the point to 
be about \ " wider than the finished 
toe. 

Have a heavy former made like 

'Fig. 94 



figure 95; the opening being -fa" 
wider than the thickness of the bar. 
The outside and the bottom of the 
opening must be just the shape of the 
end of the bar before giving the. 
crown curve. The two lugs on the 



Fig. 95 




top should be pretty heavy. The 
wedge must drive as shown in the 
figure. If driven in the opposite 
direction it is apt to jar out. The 
operation of this former is so obvious 
that further description is unneces- 



SMITHING. 125 

sary, except to say that it is of rough 
cast-iron, needing no cleaning except 
in the slot. 

The former for the complete shape 
is shown in figure 96. 

Fig. 96 

3C 




Heat the bar throughout. Lay it 
on the former in the position shown* 
in the dotted lines. Key it up tightly 
by the key a. Then wfth a cam-lever, 




shown in figure 97, which is pivoted 
by its pin in the hole c of the former, 
the bar can readily be set to its curve; 
the lever being swung first to the 



126 BOILER MAKING. 

inside and then to the outside. The 
lip of the former must be made the 
same height as the thickness of the 
bar, to allow of flatting down in case 
of buckling. While the bar is being 
held to its curve by the wedge and 
cam-lever, knock down the ends to 
meet the former. It is surprising 
how quickly bars can be shaped by 
these contrivances. A furnace adapt- 
ed to heating such bars, of which 
there are several good ones in the 
market, should be in the plant of 
every boiler shop. They are not only 
useful for this particular purpose but 
for a great many other details. 

After getting the crown bars into 
shape, it requires but the welding of 
the ends to make complete. Do not 
attempt to weld both ends at the same 
time. 

To make a " flanged" tee like figure 
98, first double up the plate, setting 
the fold down close. Then drop the 
folded edge into the slot of a former 



SMITHING. 127 

like figure 99. Spread and flat dow 
the edges. The depth of the slot 
must be about ^" greater than the 
height of stem required. The stem 
will lose about that amount in cool- 
ing. The wings of the former must 
slope away from the slot -J" in 6". 
This is exaggerated somewhat in the 
cut to show it more plainly. 



Fig. 98 Fig. 99 




If curved tees are required, flange 
them first in the straight former, then 
bring them to the curve desired in a 
second former of the proper shape. 
Do not attempt to make them entirely 
with the curved former, as it is impos- 
sible to drive the stem down to the 
bottom for the full length ; for, no 
matter how hot the metal is, it will 
persist in buckling. If the tee is in 
tended for the waist of a locomotive 



128 BOILER MAKING. 

boiler, where the rise of the wagon 
top causes the flanges to be twisted, 
it is best to fit them separately into 
their places. Having the centre of 
the tees made to the proper curve, 
very little work will be required to fit 
them, and it is impossible to make a 
boiler that will be exactly true to the 
curve called for. Indeed, some boiler 
makers fit the tees to the boiler from 
the straight, not attempting to curve 
them at all beforehand. Others think 
much time is saved, especially where 
the doubling, flanging, and curving 
are all done at one heat ; and it can 
be. The inside of a boiler is an awk- 
ward place to work, and the less re- 
quired there the better. 

To make an eye or jaw upon a 
brace, two methods may be taken ; 
viz., upsetting the rod until enough 
stock is made up, and welding on a 
stub of larger section, or smaller rods 
doubled around and lap-welding on. 
Ordinarily, welding in boiler work is 



SMITHING. 129 

objectionable, and should not be al- 
lowed where it can be avoided, unless 
upsetting is the alternative, especially 
in this matter of brace jaws and eyes. 
Much as has been said and written to 
the contrary notwithstanding, a prop- 
erly welded eye or jaw is as good as, if 
■not better than, the upset ones. By 
" properly welded" is meant not only 
that the welding should be well done, 
but that the joint should be properly 
designed. It may be asked, What 
designing can tfiere be in a weld ? 
The answer is, that there is just as 
much designing required in making a 
weld as there is in any other detail in 
the boiler. Take for instance a i-J" 
rod. Upset the ends to be united a 
little, and draw them out to the usual 
angle of 45 degrees, and we have a 
surface for welding of about i|- square 
inches area. Now suppose the joint 
was badly welded, and has a flaw in 
it of one half the area, which leaves § 
square inch area, or about 25 per 



130 BOILER MAKING. 

cent less than the cross-section of the 
rod. Now change the design, and 
instead of drawing out to the usual 
angle, the upset is drawn to a taper 
of 2" in length, and the ends are 
lapped 4" and welded. This gives 
an area on the joint of not less than 
3-J square inches. If then one half of 
the joint is a flaw, we still have more 
than double the area of the rod, un- 
less the whole of it is at one end, 
which is very unlikely. Eyes and 
jaws made up on this plan of a long 
weld have proved themselves under 
test to be stronger than the rod. 

On the other hand, to upset suffi- 
ciently to make stock enough, if the 
rod is at all fibrous (and what rolled 
metal is not ?), the fibres are so driven 
back and buckled upon themselves 
that more or less of them part com- 
pany, leaving numerous little flaws, 
and the fibres in any direction but that 
of the strain. 

A short time since the author made 



SMITHING.. 131 

a comparative test of the strength of 
jaws made by the two methods. 
Having no proper testing machine or 
dynamometer, the only result attain- 
able was where breakage occurred. 
The rig used was composed of a stout 
lever and a lot of pig-iron. Six jaws 
of each kind were tested. They were 
all practically of the same cross-sec- 
tion in the rod and around the eyes. 
In every case the made-up and welded 
jaw broke the rod, while but one of 
the upset ones broke there. One up- 
set failed between the eye and the 
rod, at a point apparently the strong- 
est. The other four failed at the eye, 
the failure in each case being so sud- 
den that, although the closest atten- 
tion was given to it, it was impossible 
to say whether the rent started from 
the hole or from the outside. On 
placing the pieces together they 
fitted perfectly, showing that no set 
whatever was given by the strain be- 
fore or during the breaking. It may 



132 BOILER MAKING. 

have been that the square rod used in 
the made-up jaw was of better ma- 
terial than the rods; but the price, 
which is usually a good indicator of 
quality, said it was poorer, it costing 
one-half cent per pound less. The 
rods were all of the same batch. 

The jaw most in use is made of f" 
square iron on a i-J" diameter of rod, 
with the eye -Jf" diameter. In fact it 
is used so often that it is practically 

Figs 100 Fiff- 101 

s * lilH UIb** 

^ * V ~Ttrmn^ 

the standard in land boilers. See 
figure 56, ante. 

To form this jaw take a f" square 
rod about 30" long, and double it up 
in the middle as in figure 100, and 
draw the ends out tapering on the 
flat way for a distance of 3" or 4". 
Double again in the transverse direc- 
tion with a ^|" pin in the fold. Let 
the ends remain open as shown in 
figure 101. Prepare the rod by up- 



SMITHING. 133 

setting a little at a point distant from 
the end equal to the length of taper 
given to the jaw. Draw the end to a 
wedge shape, leaving the point £" 
thick. It will appear then as in figure 
102. Now bring both parts to a weld- 
ing heat. Be careful not to allow the 
heat to run too far up the jaw part. 
Keep the pin in the eye as you weld 
up, so as to prevent its closing. Weld 

Fig. 10 &^ Fig. 103. 




with a rush, and do not tinker over it 
to make it look pretty. Every blow 
given after it loses its redness 
weakens it. Be very sure that the 
rod lines with the centre of the eye. 
It will now appear as in figure 103. 

The next operation is to open the 
jaw; which can readily be done by 
heating close to the weld, and spread- 
ing enough to allow a block of a 
thickness to correspond with the foot 



134 BOILER MAKING. 

used, and having a hole at the proper 
distance from the edge for the pin to 
pass through. Drive the block in so 
that the pin will enter and flat the 
jaw down. 

In making a crowfoot brace, never 
weld the rod to the foot by " jump- 
ing" it on. It is very apt to leave un- 
expectedly. The jar of riveting will 
frequently start them. The most 
secure method is to hot-punch a hole 
through, and upsetting the rod, thread 
it through and weld up on the back 
side ; the parts before welding ap- 
pearing as in figure 104. 

"Fig. 104 



An anvil block with slot to allow 
the rod to drop into, so that the edge 
of the foot is below the top of it, also 
having a sufficient face to lay the foot 
on, will be very convenient for this 



SMITHING. 135 

work. Such a block is shown in 
figure 105. 



Fig. 105 




To' weld the rod to the other foot — 
or hand, as it might better be called — 
allow it to lap about 3" or 4". Upset 
and taper the rod as shown in figure 
102. The foot itself requires no prep- 
aration. 

About the only place where welding 
by jumping is allowable about a boiler 
is at the corners of fire-box rings, or 
casing bars as they are sometimes 
called. As there is comparatively lit- 
tle strain upon them from the steam 
pressure, the great point is to get 
them water-tight. Jumping, if care- 
fully done, will do this quite as well 



136 BOILER MAKING. 

as if a more expensive lap-weld were 
made. 

Cut the long bars to the outside 
length required, and jump short pieces 
upon the ends, so as to. make two half 
frames as shown in Fig. 106. The 
short pieces on the ends must be 
long enough to allow for welding 
when the two halves are brought to- 
gether. Trim and finish the corners 

Fig. 106 



completely before uniting the halves. 
By making up this way in halves 
much time is saved, as the Work is 
lighter and of course easier to handle 
while finishing the corners. 

In welding together allowance must 
be made for the shrinkage in cooling. 
This is an indefinite amount. A good 
average allowance is -fa" per foot 
from side to side when the work is 



SMITHING. 137 

red hot. ■ If on cooling it is found 
not just right, a very little drawing 
or upsetting will be required to bring 
it to the proper dimension. 

In some locomotive boilers where 
the axles are under the fire-box, a re- 
cess or pocket is required on the out- 
side of the box. This necessitates 
cutting the bar out for it. This can 
be done with hot-chisels, but it is as 
much as fifty per cent cheaper to have 
it done on a slotter. This element of 
cost must be reckoned not only from 
the smithing out, but from the fit- 
ting in of the plate and calking, the 
machined spot being square and 
curves fair. Indeed, some railroads 
require these rings to be machined 
all around inside and out, which makes 
a splendid piece of work, but rather 
an expensive one. 



x. . 

PUNCHING. 

Punching, besides the necessary 
machines, punches, and dies, requires 
plenty of room and light. Conven- 
ient contrivances for handling the 
plates are indispensable for the qual- 
ity as well as the quantity of the out- 
put. No satisfactory result can be ob- 
tained where it requires three to a 
half dozen or more men to hold the 
plate up to the punch by main strength. 
This is a method often seen in boiler 
shops. Nor is it any great economy 
to hang a plate up by chains or bail- 
hooks and require one or two men to 
teeter it around while hunting the 
center point of the punch with a slate- 



PUNCHING. 139 

pencil line on the plate, and that line 
half rubbed off; though this is a great 
improvement on the first-mentioned 
method. 

A much better arrangement is to 
have a good-sized table surrounding 
the machine, with a ledge all around 
it i\" high. On this table place a 
number of cast-iron balls about 2" in 
diameter; the height of the table to 
be such that the balls will support the 
plate to be punched just clear of the 
die. A plan showing about the rela- 
tion of the table to the -machine is 
given in Fig. 107. 

The table should be plated with \" 
iron to make a better surface for the 
balls to roll upon. The ledge around 
it should also be covered with sheet- 
iron to save wear. Between the inner 
edge of the table and the front of the 
machine there should be a lifter, ope- 
rated by a treadle-lever, reaching to 
the front of the table, for the purpose 
of lifting the plate to meet the center 



140 



BOILER MAKING. 



point of the punch. It is a fact proved 
by experience that two men can handle 
a plate on this table that would re- 
quire ten or a dozen men to place 
there, and punch from twenty-five to 




fifty per cent more holes than by the 
aid of any other arrangement. This 
table can be built at an outside cost 
of thirty-five dollars. 

In preparing a plate for punching, 



PUNCHING. I41 

the center lines for the holes should 
be very distinctly marked, and every 
center gone over with a prick-punch. 
Give the prick-punch a light trial tap 
at first to sft that the proper place is 
hit. If it is, give the punch a good 
solid blow, taking care that the dent 
is not made so large that the centering 
point on the machine punch will float 
around in it. If the proper spot is 
not hit at the trial tap, cant the prick- 
punch over and drive it sideways until 
the point reaches the proper place 
and then holding it against the shoul- 
der at the end of the little groove cut 
by the drawing over, give the finish- 
ing blow. t 

If great care is not taken in center- 
ing the holes, it cannot be expected 
that the punching will be first class. 
The machine hands have quite a 
plenty to do to steer the plate to the 
center-punch marks without being 
called upon to climb all over the plate 
to see whether the punch will come, 



142 BOILER MAKING. 

down in its proper place when the 
prick-mark is out. 

In case there are a number of plates 
of the same size, it would be well to 
have the rows of rivet holes laid off 
on wooden templets 3" or 4" wide 
lave the cen- 
These tem- 
plets can be clamped upon the plates 
to be punched, and a prick-punch, 
turned to fit the holes, can be used 
with great rapidity. These templets 
should be saved as records, or to 
use in duplicating a plate in case of 
repairs. For tube plates a board tem- 
plet covering the whole plate so as to 
be set by the edge of it, and having 
center holes to locate all the rivets, as 
well as tube holes, is a desideratum 
even for a single boiler, as by its use 
on both plates it will be almost impos- 
sible to get the tubes in crooked. 

A bad practice in many shops, and 
one that cannot be too heartily con 
demned, is the marking off of rivet 



PUNCHING. 143 

holes with a bit of pipe dipped in 
white lead. Proper enough, certainly, 
where the punch has no center point 
to center by, but it should be used in 
no other case. It is a good plan, how- 
ever, to go over the plate with it after 
the prick-punch has been used, mark- 
ing a circle about each center, as it 
will save time on the machine, more 
especially if the machine is in a dark 
corner or the day is dull. • 

The plate should not be trimmed 
before punching, as it frequently hap- 
pens that some few holes come just on 
the edge of the plate, and the punch 
is in danger of breaking if an attempt 
is made to punch half a hole. It is 
very easy to trim off to the center of 
the holes after the punching is done. 

In punching heavy plate and light 
plate with large punches, it is neces- 
sary to keep the punches cool with 
oil or oil-soap, as the heat caused by 
the compression of the metal is very 
apt to draw the temper of the punch. 



144 . BOILER MAKING. 

The faces of punches for plain holes 
are made flat, flat with a centering 
point or having a spiral shearing 
edge. The two first named are alike, 
but for one having a centering point. 
The flat face without the centering 
point is fast becoming a thing of the 
past. More time is wasted in setting 
a plate for a hundred holes than would 
pay for the punch with the centering 
point. Except for the centering point 
the faces of both should be perfectly 
flat. If made hollow, the edge is 
weak and is liable to break off at any 
time; and if made convex or conical, 
it requires much greater power to 
drive it through the plate, and a 
larger opening in the die as well. 

The spiral shearing punch, Ken- 
nedy's patent, has a face cut out in 
such a manner as to form a spiral on 
the edge, as shown in figure 108. 

The figure shows a double cut, such 
as is preferred by the patentee. There 
have been punches in the market with 



PUNCHING. 145 

but a single cut, but they are appar- 
ently infringements on Kennedy's 
patent. The peculiar advantages of 
the spiral face is that it acts in the 
manner of a shear. The only portion 
of the face that actually punches is 
the narrow flat portion which backs 
up the entering edge. As the punch 
shears or cuts the plate instead of 



■jB*ig s lOS 




rending the fibers, less strain is 
thrown upon the machine, and the 
plate about the holes is strained to so 
slight a degree that it is unnecessary to 
anneal. From experiments made by 
the chief surveyor of Lloyd's Register 
of British and Foreign Shipping it 
was shown that the ductility of plate 
punched with the spiral-faced punch 
was over 50 per cent, greater than 



146 BOILER MAKING. 

when punched with a flat-faced one, 
and the power required to drive the 
punches was nearly 50 per cent, in 
•favor of the spiral-faced. Also in 
several experiments where two holes 
were punched in the same test piece, 
one with the spiral and one with the 
flat, the test piece broke invariably 
through the hole punched with the 
flat punch. 

The author's own experience has 
shown that from lack of power a ifV 
flat punch could not be driven 
through a -J" plate ; but when a single 
cut spiral punch was used, no diffi- 
culty whatever was found. Holes as 
large as 5" diameter have been made 
with a spiral punch, and with no more 
apparent strain on the machine or 
greater power used than shearing a 
straight cut of a length equaling its 
circumference. 

Punches should not be made on a 
stock, but should be cut short and 
united to the stock by a coupling nut. 



PUNCHING. 147 

This will save great trouble in chang- 
ing punches, as the stock and nut may 
be made to suit a large punch, while 
the butts of the smaller ones can be 
made large enough to fit the same. 
Figure 109 shows the arrangement 
with nut in section. 

Fig. IO 9 




Punches should be made tapering 
■fa" per 1" of length for clearance. 
Dies yV" per 1" on the same ac- 
count. 

The diameter of dies for the mini- 
mum power to drive the punch, as 
determined by Messrs. Wm. Sellers 
& Co., may be found by the formula 

D = d(.2t), .... 8 

where D = diameter of hole in the die, 
d— diameter of punch, 
t == thickness of plate. 



148 BOILER MAKING. 

This makes a considerable taper in the 
hole, which is objectionable because 
of the loss to the plate left standing, 
with no gain to the rivet's strength. 
It also requires quite an amount of 
upsetting to make the rivet fill the 
hole. Some boiler makers use a die 
of but half the clearance given by the 
formula, under the mistaken idea that 
the gain in plate area is a gain in 
strength : which is not so, unless the 
plate is thoroughly annealed, or a 
spiral punch is used. The patentee 
of the spiral punch uses the formula 

• D — d-\- (.1/),. . . . 9 

finding so little difference in power re- 
quired, that the gain in plate strength 
was equal to the amount saved. 

Tube holes should not in any case 
be punched to full size. With a 
spiral punch allow ^" in diameter for 
riming, and with a flat punch have 
the hole no larger than is necessary 
for the teat on a counterboring tool. 



PUNCHING. 



149 



For the riming and counterboring of 
tube holes see Chapter XI. 

All 'punched holes should be laid 
off on the faying surface so that the 
holes may be punched from that side. 

ms* no 



They should also be countersunk 
slightly on the outside to take off the 
wire edge left by the die. Figure no 
is a section showing a properly fitted 
hole. 



XL 

DRILLING, ETC. 

In boiler making, as well as in 
machine work, there is no one opera- 
tion upon which the condition of the 
tools has so great an influence as in 
drilling, and its kindred operations 
counterboring, countersinking, and 
riming. The tools should not only be 
sharp, but of proper form. The an- 
gles and equality of the cutting edges 
should be particularly looked after. 

For drilling, the' " twisted " tool is 
the best and cheapest — not for first 
cost, but for the amount of work ob- 
tainable. Once made, it can be worn, 
ground, reworn and reground, until 
nothing but the stock is left, and it 
is always to size and the cutting 



DRILLING, ETC. 151 

edge just the right angle for the 
best effect ; whereas the flat drill is a 
constant source of expense for dress- 
ing, to keep to width, and is very 
difficult to grind to the proper angle, 
seldom being much better than a 
scraper. To be sure it requires a 
good mechanic to keep twist drills in 
order, but the difference in the result 
obtained will more than pay for his 

mg. 111 




keeping. It would be well to have all 
small tools kept in order by one com- 
petent man, allowing no other person 
to sharpen or dress them. 

Countersinking tools should be 
made With a teat, so that they will 
always work central. They can be 
made with a stock to fit the same 
socket as the twist drills. A neat and 
effective tool is shown in figure in, 



152 BOILER MAKING. 

which is a copy from one designed 
for |f" holes, and was very handy 
and economical. The cutter a is \" 
thick, \\ n long, and is kept in place 
by the set-screw b, which is -§-" diame- 
ter. The collar c is driven on, and if 
worn can readily be renewed. The 
two parts -cutter and collar are the 
only ones subjected, to wear, and for 



Fig; 112 




the amount of work done by them the 
cost of maintenance is merely nomi- 
nal. An important point in this tool 
is to have the stem a little smaller 
than the collar, so that the chips may 
have a clearance. In the one spoken 
of the body was \\" diameter. 

For counterboring tube holes a 
tool like figure 112 is used. This 
also has a collar on the point to allow 



DRILLING, ETC. 153 

of renewal for wear. The cutter 
is notched out to fit the stem, like a 
gib, so that it may center itself. The 
slot in the stem must be long enough 
for the cutter to pass through easily. 
The stem should be pretty stout, as 
the cutter to be stiff enough to stand 
up to its work must be not less than 

Fig; 113 




■J" thick for 2" holes or less, and ^g-" 
thicker for every inch larger than 2". 

For rounding the edges of tube 
holes the same style of tool may be 
used, with the cutter made in the 
proper shape ; the cutting edge start- 
ing flush with the side o.f the collar, 
as shown in figure 113. 

The drilling machine should be an 
overhead one, leaving the space all 
around clear for swinging the plate. 



154 BOILER MAKING. 

The feed is best worked by a rack 
and pinion movement, and operate, 
through.a levis wheel on the pinion 
shaft, by a continuous chain with 
hooked shifting weight. 

A ball table such as described for 
the punching machine is a good thing 
to have under the plate drill. It 
should have a space cut out on one 
side, so that the operator may get to 
the drill handily. 

Fluted rimers for holes in plate 
metal should "never have the cutting 
edges an equal distance apart. Were 
they equal, it would be almost im- 
possible to obtain a round hole. No 
matter how many flutes there- are, if 
equally spaced they are sure to jump, 
so that a tap could not follow and 
make a perfect thread. No partic- 
ular care need be taken in laying 
them out. A good way is to space 
them by "thumb" measure, and no 
trouble will be found in getting a 
truly circular hole. 



XII. 

TRIMMING. 

All trimming of edges, except* 
thinned corners, should be done be- 
fore setting up. To chip edges with 
the plate in place, without injuring 
the under plate, is a slow and expen- 
sive process, and where it is impos- 
sible to avoid it none but the most 
careful and experienced hand should 
be trusted with it. 

The angle to which the edges of 
plates should be trimmed is about 
120 degrees. This is found from long 
experience to be the most convenient 
for calking, and chipping while in 
place. See figure 114. 

All holes that can be, should be 
punched or drilled before trimming. 



156 BOILER MAKING. 

Never use a hammer and chisel when 

it is at all practicable to machine the 

edges of plates. For planing straight 

Fig. 114 



./ 



/ 

JZ 



J 



work the best machine is that on 
which the plate can be clamped down 
solidly in its full length, and the tool 
traversed back and forth by a screw. 
It is important that the plate should 
lie flat for planing, as the tool cuts 
the edge to an angle; and if the plate 

Fig. 115 



buckles up, it will cut deeper and 
thereby make the lap narrower than 
it should be. Or, if this point is 
taken care of, that part of the plate 
which is held down will be wider than 
is necessary. Figure 115 shows how 
this effect is produced. 



TRIMMING. 157 

Circular heads can be trimmed to 
advantage on an ordinary boring mill 
or large facing lathe ; while the 
straight part of other flanged work 
can be trimmed on a planer. Too 
many boiler shops lack these machine 
tools. Where the boiler shop is con- 
nected with a machine shop it is far 
cheaper to carry a plate to the boring 
mill or planer, and have all possible 
work done by them, instead of chip- 
ping them. Even where the planer 
must necessarily leave considerable 
for chipping, it gives the chipper a 
better guide for width and angle, and 
neatness as well, for without thinking 
of it he will endeavor to emulate the 
work produced by the machine. 

Corners where spread for intersect- 
ing laps should not be trimmed until 
after the plate is riveted into its 
place, as they frequently require a 
little upsetting to make them fill the 
space, and a "dutchman" should be 
an unheard-of makeshift in boiler 



158 BOILER MAKING. 

work. Or it may be that a little 
more thinning is. needed, in which 
case the work of trimming them pre- 
vious to fitting in would be thrown 
away. 

Flanged plates should be laid upon 
stout trestles or blocks, and have a 
few hundredweight piled on them to 
keep them steady. The trestles or 
blocking ought to be high enough' to 
allow the men to stand to their work. 
Standing they can get a good free 
swing of the body to counterbalance 
the throw of the arm and hammer. A 
sitting posture, which is compelled 
by having the work too near the floor, 
is conducive to fatigue, as it throws 
too much work on the muscles about 
the waist, and cramps the legs so that 
a frequent letting up is required for 
resting and stretching. Keep the 
men on their feet, and they will do 
double the work and not notice it. 



XIII. 

COLD BENDING. 

A plate should never be bent cold 
with hammers or mauls. The best 
of metal will be ruined thereby for 
use in boilers, unless 'it is afterwards 
annealed, and even then nothing but 
the very best can be relied upon. If 
the metal is cold short it is more than 
liable to crack through, and a ham- 
mer will cut such dents as to mate- 
rially weaken the most ductile. The 
better way, if rolls are not at hand to 
do the bending, is to leave the boiler 
unbuilt, as in that shape it is certain 
not to burst, whereas with cold ham- 
mer-bent plates it is almost certain to 
burst unexpectedly, sooner or later. 



160 BOILER MAKING. 

Cold bending should be closely 
looked after, as the symmetry of the 
work as well as the fitting together of 
the rings of circular shells depends 
greatly upon the accuracy with which 
the bending is done. * 

The rolls should be stiff enough not ■ 
to spring to any appreciable extent 
while doing their work. The upper 
roll must be arranged so that it may 
be easily removed by shipping it on 
end. To do this the upper part of 
the housing or frame at one end 
should be removable. A good way, 
that saves considerable work, is to 
have it so pivoted on one side that by 
slacking a nut on the opposite it may 
be swung sufficiently to one side to 
allow the roll to pass by. 

Large cast-iron rolls should be cast 
with a central core to take out some- 
what of the internal shrinkage. A 
solid roll will break with less than 
half the strain that it takes to break 
one having its center cored out. 



COLD BENDING. l6l 

The ends of the shifting roll should 
be fitted with eye-bolts to hook the 
lifting tackle to on swinging it in and 
out of place. 

The rolls should have a reversible 
motion, . so that the plate can be 
worked back and forth until it comes 
to the proper shape. 

Having the plate punched and 
trimmed as far as practicable, it is 
then ready for the rolls. Raise the 
top roll sufficiently to allow the plate 
to run through easily. Carry it on to 
the middle, then screw down as hard 
as possible on the roll bearings, and 
before starting the machine see that 
the plate is set -square to the rolls. A 
large wooden square of a parallel 
thickness, pushed into the angle 
formed by the top roll and the plate 
as a base, is handy to correct with. 
Cut a sheet-iron templet to the exact 
curve the inside of the plate is to be, 
and in length about equal to the 
radius. Roll the plate back and 



l62 



BOILER MAKING. 



forth, screwing down on the roll bear- 
ing each time it is rolling in the same 
direction it started in — carefully test- 
ing it from time to time with^ the 
templet. 

Take good care not to roll it small, 
for it is a difficult job to spread it, 

Fig. 116 




more especially if it should be but a 
short section that is quick of the 
curve. If it should be left a little 
large, it can be sprung together by 
passing a chain loosely about it and 
drawing up the slack by twisting it 
with a bar. 

Where large openings come in the 



COLD BENDING. 163 

plate, such as for domes or manholes, 
the waste piece should not be cut out 
entirely before the bending is done. 
It should be left united to the plate 
by four short sections to be chipped 
out after bending, as shown in figure 
116. If this piece is left out the plate 
will bend very short opposite the 
opening, as it will lose in stiffness 
directly in proportion to the space 
cut out. 

Be very careful, as the end of the 
plate approaches the roll, not to let it 
run by, or it will snap out and fall so 
quickly as to endanger the lives of 
any within its reach. 



XIV. 

SETTING UP. 

The setting-up floor should be spa- 
cious, and provided with powerful 
cranes, chain slings, hand hoisting 
machines or tackle, portable stages, 
and plenty of blocking. Rivet-heat- 
ing forges and one or two open forges 
should be disposed in convenient 
places. The roof framing should be 
strong enough to support a consider- 
able weight depending from a fall or 
other hand hoist, unless there is a 
traveling crane which commands the 
whole floor. Over the power riveter 
there should be quite a tower, in the 
top of which a traveling crane of 
small range, say of ten feet or so, 
each way, for ordinary work. The 



SETTING UP. 165 

lift should be considerable — not less 
than thirty feet. This crane should 
be arranged to be operated entirely 
from the floor, so that the operator 
may be near the work and see just 
how much or little to shift it himself. 
In setting up a boiler it is impor- 
tant that every part is fairly matched 
to its neighbors, and also that it is 
properly in line. Nothing looks worse 
than a long cylinder boiler "sway- 
backed," like a country horse ; or 
"hogged," because it was put to- 
gether in a . harum-scarum fashion ; 
or a dome hanging to one side; like a 
gambler's hat. 

' The horizontal seams of cylindrical 
boilers should be riveted before the 
sections are brought together. On 
bringing them together it is frequently 
found that instead of being perfectly 
circular, they are somewhat oval, and 
do not match. To get over this, 
pass a long bolt through two opposite 
rivet holes, across the long diameter s 



l66 BOILER MAKING. 

and draw on them so that one section 
will enter the other. After sliding 
together till the bolt ends foul, take 
out the bolts, and if the sections still 
bind so as to be difficult to get them 
further, take a chain fitted with a 
hook at each end — bail hooks are the 
best — and hook over the outer edges 
of the two sections, and twist up the 
slack with a piece of scantling or 
wooden handspike. . An iron bar is 
not so good, as the chain is apt to slip 
on it. A special contrivance for this 
purpose is shown in figure 117. An 
ordinary chain sling may be used in 

Fig. 117 



connection with the screw jack shown;, 
though one with a " bail hook " is pref- 
erable to a plain-hooked one, as being 
less likely to mar the trimmed edge of 
the plate. 

After getting the sections together 



SETTING UP. 167 

and lightly bolting through the rivet 
holes, the end 'sections should be 
leveled and lined with each other." 
Through a rivet hole in the top and 
bottom centers a plumb-line can be 
passed and the section's set vertically 
thereby. Having the end sections 
blocked firmly in position, it will be 
very easy to straighten up the inter- 
vening ones with a lining cord, start- 
ing with the next ones adjoining the 
ends. When two adjoining sections 
are properly lined, look for a few 
rivet holes that come exactly fair. If 
the laying out and punching has been 
done in a reasonably proper manner it 
will not be difficult to find sufficient 
for the purpose. Into these holes 
drive tightly fitting bolts, and set the 
nuts up solidly. By these means it is 
pretty certain that the boiler will be 
straight, though it would be well to 
prove it by going over it again with 
plumb-line and cord. If all is straight, 
set in the heads, being careful that 



l68 BOILER MAKING. 

they are square with the barrel, and 
also that the lines of tube holes — if it 
be a tubular boiler — are level. Every- 
thing being in line, plumb, level, and 
square, put a clamping bolt into every 
third or fourth rivet hole, and clamp 
up tightly. These clamping bolts, and 
the steadying bolts as well, must re- 
main until it is necessary to remove 
them to get in the rivets. 

Where a machine is used for rivet- 
ing, more than two sections cannot 
usually be put together at a time, as 
there is a limit to the length of the 
stake or ''holder-on" of the machine 
beyond which it cannot reach. In 
such a case each section must be lined 
independently as it is put in connec- 
tion with the next preceding one. 
This can best be done with a straight- 
edge, taking care that the section being 
lined in is not oval at its outer end. 
Draw in its long diameter, and hold it 
there until it is fully riveted in, if such 
should be the case. The head having 



SETTING UP. 169 

its flange turned in should be first riv- 
eted in on starting. Boilers having 
one head with flange turned in and 
the other with flange turned out can 
have every rivet driven by the machine 
except, certainly, such as hold the 
stays to the shell. 

In a locomotive type of boiler the 
fire-box must be completely riveted, 
the crown bars fitted and bolted on, 
and the calking all done on the outer 
or water side : — the inner or fire side 
to be left without calking till all riv- 
eting and stay-bolt setting is done. 
The fire-box shell must be riveted up, 
except the front or throat plate. Then 
set them together. Tie them there 
with a few bolts running through the 
stay-bolt holes. Now see that the 
door flanges match. If the former 
was properly made, the male flange 
will be found a little small. To spread 
it to fit, have a number of iron blocks 
heated white, and lay them against 
the door flange. This will heat the 



170 BOILER MAKING. 

flange in a very short time to a red, 
when it can readily be spread to fit. 
Do not attempt to spread if it does 
not show at least a red glow. Espe- 
cially with steel a black heat is a dan- 
gerous one, and sometimes even a 
light blow will crack it. It would be 
easier on the plate to pien it out cold 
than to attempt to draw it at a black 
heat. 

Before riveting the fire-box into its 
shell, have the barrel fitted and lined 
to it, and securely clamp-bolted. If 
the flat sides of the shell bulge out- 
ward, it will be necessary to draw 
them in with long bolts through the 
stay-bolt holes. If one side is flat or 
hollow while the other bulges, use a 
stiff piece of timber on that side, 
reaching from end to end, through 
which run the clamping bolts. The 
hollow side can be drawn out by the 
same piece of timber, by using short 
bolts having a bent end, instead of a 
head to hook through the plate. All 



SETTING UP. I7i 

such clamping arrangements must be 
kept on until all stay-bolts are set 
that can be without their removal. 

The fire-box with its shell being set 
up, level fore and aft, and its center 
plumb, bring the barrel portion into 
place. If the boiler is of the raised ■■ 
wagon-top variety, the upper connect- 
ing or offset plate is not put in place 
until all the rest is properly set and 
firmly secured, when it can be tried 
in and the rivet holes marked on it. 
It is best to mark them with a cen- 
tering punch, which is made to fill the 
hole in the other plates. It is then to 
be taken out, punched, and trimmed^ 
when it can be put back permanently. 

To get such a boiler in line sidewise 
place a straight-edge on each side of 
the fire-box, to extend as far as the 
forward end of the barrel ; drop a 
plumb-line through the vertically cen- 
tral rivet holes, and measure from the 
line to each straight-edge. Longitu- 
dinally, level each section, or if the 



172 BOILER MAKING, 

blocking is so arranged to get through 
pass a straight-edge under the fire- 
box and measure up from it the 
proper distances to the under side of 
each barrel section. 

To plumb the fire-box, when the 
upper part is wider than the lower, 
throw a line over it with a " bob" on 
each end, and see that the distances 
from the line to the sides are equal. 

Leave the dome off until all else is 
riveted, as it is very convenient to turn 
the boiler on its back while riveting 
and calking the under side. 

Rolling over a boiler must be in- 
trusted to none but the most careful 
and reliable men. A little careless- 
ness may necessitate quite costly re- 
pairs. The author has seen a large 
steel locomotive boiler so badly in- 
jured by falling against another that 
the shell plate of the fire-box was 
knocked in, the stay-bolts driven 
through the inside plate, and the 
crown plate all buckled up. . It cost 



SETTING UP. 173 

nearly half the selling price to repair 
it. The riveting had all been done, 
and it was necessary to cut out the 
fire-box to get at the crown plate. 

A fall or set of falls should be used 
on both sides in turning over — one for 
hoisting and the other for lowering. 
The lowering must be done slowly. 
If there is the least doubt of the 
strength of the tackle or the framing 
from which it is suspended, keep 
blocking under the boiler, taking ou[ 
a little at a time as it descends, or 
adding as it ascends; allowing but a 
few inches fall in case of accident. 
Take no chances, for not only the 
boiler is in danger of injury, but life 
and limb as well, 

Give the boiler no chance to slide 
sidewise on the floor as it rolls down. 
This is a fruitful cause of accident ; 
for when it does happen, it is as sud- 
den and vicious as the kick of a mule, 
and will try the strength of every- 
thing supporting it very severely. 



174 BOILER MAKING. 

In setting up a cylindrical boiler 
with furnace flues and back connec- 
tion, like that shown in section in 
figure 1 6, page 34, have the shell and 
front head set up and riveted as for 
a plain boiler. The flue and back 
connection, set and riveted together, 
are then put in place, and the flues 
riveted to the front head. Be sure to 
set the back connection properly, so 
that the tube holes will line perfectly 
with those in the front head, other- 
wise there will be trouble in setting 
the tubes. Lastly, put in the back 
head. 



XV. 

CALKING. 

The object of calking being simply 
and solely to produce a "stop water," 
when that is attained no further bene- 
fit can accrue from it. But great evil 
may arise from over driving, to which 
there is a great tendency as usually 
practised. Besides its bad effect upon 
the work, it is a useless expense of 
both time and the hardest kind of 
labor. 

There are two prominent styles of 
calking in vogue — the square and the 
concave. Figures 118 and 119, page 
177, show sections of joints illustrating 
them, and the tools by which they are 
produced. Figure 120 is an orna- 
mental style said to combine the ad- 



I76 BOILER MAKING. 

vantages of both. Figure 121 is the 
same as figure 118, but has the acute 
corner slightly rounded, so that it will 
not cut the under plate. Figure 118 is 
the easiest to work, and the tool is of 
the least trouble to keep in order, but it 
will nick or groove the under plate with 
its sharp edge. The sharp corner of 
the tool is first used outward to "split" 
the plate. Then the tool is turned 
over and the work finished in the 
shape shown. 

Figure 119 will not cut the under 
plate, but there its advantage stops, for 
it is very hard to drive ; in fact, with 
heavy plate it requires several sizes — a 
small one tp start the groove, and one 
of proper size to finish, with several 
intervening sizes to bring it up gradu- 
ally. 

Figure 120 appears to be as hard to 
drive as a smaller size of 119, while 
there is yet a square corner to mar the 
under plate. It is claimed that this tool 
makes very handsome-looking work. 



CALKING. 



177 




178 BOILER MAKING. 

What good beauty does when covered 
up by brickwork or non-conducting 
material is a question ; and covered 
up all first-class work is; 

Figure 121 is as easy to drive as 118, 
and as it does not mar the under plate 
any more than 119, its advantages are 
certainly greater than that. 

" It is claimed by the patentee of the 
concave calking that the plate is up- 
set to a considerable distance from 
the edge ; "one half to three quarters 
of an inch" producing a bearing which 
" increases the strength of the joint." 
If this were a fact it would be a good 
thing ; but does driving a wedge into 
such a place keep the plates together? 
Will it not rather throw an uncalled- 
for strain upon the rivets, which are 
already loaded pretty well by their 
shrinkage strains ? But does this state 
of things exist ? The author deter- 
mined to let the work speak for itself. 
A single lap joint was riveted up from 
§" steel plate, and three styles (fig- 



CALKING. 179 

ures 118, 119, and 121) of calking done 
upon it. It was then cut crosswise of 
the- joint into six pieces; the faces left . 
by the cutting were brought to a high 
finish, and treated with acid. No in- 
dication of compression whatever was 
shown. Believing this was because 
the steel was so homogeneous in struc- 
ture that it would show to better ad- 
vantage in iron, another test piece of 
iron plate was treated in like manner. 
The result proved to be entirely dif- 
ferent to that claimed. The upsetting 
was in no case over -^-" in depth, and 
in one case — opposite a rivet at that — 
there was quite a distinct opening of 
the faying surfaces with 119, which- 
commenced opposite the crown of the 
curve, and reached a point opposite 
the corner of the rivet head. This 
opening may have been there before 
the calking was done, but it certainly 
was not closed by it, as it would have 
been had the upsetting theory been 
correct. 



150 BOILER MAKING. 

The compression of the metal in all 
the specimens was practically equal 
in depth, but with 119 the metal flowed 
or spread on either side, producing a 
long feather edge against the under 
plate, and a slight concavity on the 
high edge of the outer, as shown in 
figure 122. 

Mg* 120 



The tools should be stiff and stubby, 
as short as is convenient to hold. 
Drive lightly, remembering that all 
that is needed is but to check the lit- 
tle pin-hole leaks, and that the rivets, 
not the calking, hold the plates to- 
gether. To drive as some calking is 
driven is equivalent to driving an 
ounce tack into a segar-box with a 
sixteen-pound sledge. 



XVI. 

TUBE SETTING. 

Because of the irregularities of the 
tube plates, which are inevitable in 
the best of boilers, it is necessary to 
measure out to out of them, for every 
tube — of course adding the extra 
length for beading. This measure is 
best taken with a piece of gaspipe, 
as it is so much stiffer for its weight 
than a solid rod or wooden staff, as 
well for its convenience for catching 
with a small rod at the farther end. 

The measuring pipe should be held 
flush by the helper at the far end, 
while being marked close against the 
plate at the near. The helper will 
find that a block of wood held against 



152 BOILER MAKING. 

the pipe while bearing on the plate 
will be much nicer than the thumb 
or palm of the hand. Use a slate- 
pencil for marking, for very little care 
is required* to preserve it as long as is 
necessary, and file marks coming. so 
near together will engender confu- 
sion. 

Try all the holes first to get as 
many as possible before marking off 
any tubes. It will be found generally 
that the lengths run in clusters, that 
do not vary much over -fa" among 
themselves, which is near enough to 
work to. These clusters can be sur- 
rounded with a chalk mark so that 
their limits can readily be found on 
putting in the tubes. 

The length required for beading is 
about two and one half times the 
thickness of the tube, and should 
never be less than twice. 

Where copper ferrules are required 
at the fire-box end, and the space be- 
tween the tubes is- less than one third 



TUBE. SETTING. 183 

their diameter, the tubes must be 
swedged sufficiently to allow room 
for the ferrule of same outside diam- 
eter as the tube. This swedging can 
best be done under a drop-hammer, 
though there are hand-power ma- 
chines that do the work fairly well. 
The ferrules should not project much 
farther beyond the plate than just 
sufficient to give them a hold, and 
allow the tube to be beaded over 
them. 

In placing the tubes, commence 
with the bottom rows and follow right 
along, the helper at the far end using 
a short rod for catching and directing 
his end into place. 

The process of expanding should 
be a progressive one. Do not finish 
setting one tube before commencing 
another. Rather take one step at a 
time throughout. 

First get the tubes fixed in their 
proper position. This is done by 
battering out with a straight-piened 



1 84 



BOILER MAKING. 



hammer— the pien being crooked 
downward ; or, better, with a tapered 
triangular plug, the angles being 
rounded off to about the shape of the 

Fig..l23 



inside of the tube. Figure 123 shows 
such a tool. This plug makes a good 
expanding tool in default of a better 
one. It is slow work, however, as it re- 
quires so many turnings. 

Fig, 124 



While setting out one end tne 
helper holds the far end at its proper 
distance from the plate. For this 
purpose a small block of iron, with a 
recess in it of the proper depth, will 



TUBE SETTING. 185 

be found very convenient. Figure 
124 shows how it is to be used. The 
bead around its edge is for conven- 
ience in handling. 

There are several good tube ex- 
panders in the market, the principal 
ones being the " Prosser" and the 
" Dudgeon." 

The Prosser expander is made up 
of a number of segments held in place 
by an encompassing spring. The out- 
side of these segments is shaped to 
such forms as it is desired to have the 
tube set to. The insides of them are 
nrade to fit a tapered mandrel, which 
is driven in with a hammer. This 
tool requires frequent loosening and 
shifting around on account of the 
spaces left between the segments. 

The Dudgeon expander does first- 
class work in a first-class manner, 
being a series of small rolls, of proper 
shape for forming the tube, forced out 
by a tapered mandrel, which is kept 
turning while being driven in — thus 



160 BOILER MAKING. 

spreading the tube with the least pos- 
sible chance of splitting it. 

The triangular plug shown in figure 
123 sets the tube more on the outer 
side of the plate than the inner, and 
in consequence does not make as 
good work as if it were otherwise ; 
yet the tube will hold the plate 
against the outward pressure of the 
steam as well as the best. 

Fig.Jf2S 



Beading is done, after the tubes are 
expanded, by means of the "boot" 
tool shown in figure 125. The long 
leg goes inside of the tube. The 
beading must be done gradually, 
working down a little, all around, at 
a time, to avoid splitting. The tool 
shown should be cocked at first so 
that the long leg lies with its full 
length against the inside of the tube, 
and gradually as. the end spreads it is 



TUBE SETTING. 187 

brought out so that the " heel " will 
set the edge close against the plate. 
Where the tubes are large, and the 



Fig.126 




spaces between them comparatively 
great, a number of them are fitted 
with nuts on both ends. Such tubes 



155 BOILER MAKING. 

should be double the thickness of the 
others to allow sufficient strength 
after the threads are cut. The thread- 
ing must be done in a lathe, and the 
sides of the nuts which bear upon the 
plate must be squared up with the 
thread. 

Figures 126 to 128 show the three 
general stages in the progress of the 
work of setting tubes. 



XVII. 

FITTINGS. 

Cast-iron, being so readily made to 
shape, is almost too frequently used 
for fittings. At the same time there 
is a vast deal of misconception of the 
proper proportions of the parts. A 
peculiar and inherent defect of cast- 
iron is the " shrinkage strain" pro- 
duced by the unequal cooling of the 
metal in casting. To reduce this to 
a minimum, all portions of the same 
piece should be as nearly of the same 
weight as possible, or the difference 
be not abrupt. For example, pipes, 
as usually made, have the flanges 
from one and one half to twice the 
thickness of the barrel, and with but 
an ordinary fillet in the corner. If 
the flange be broken off, it will be 



190 BOILER MAKING. 

found honeycombed and weak. This 
may be avoided almost entirely by 
making the fillet of a parabolic shape, 
as in figure 129. Or, if the room is re- 
stricted, it may be made of the same 
thickness as the barrel, and a number 



Eig. 129 




of short brackets cast in, as in figure 
130. 

Supporting lugs for cylindrical boil- 
ers are troubled the same way if there 
is much variation in. the thickness of 
the metal. The placing of these lugs 
should be such as to produce as little 
local strain upon the boiler as pos- 



FITTINGS. I91 

sible. The best practice places them 
not over four diameters apart. Where 
two pairs only are required, place 
them one sixth of the length from 
each end. A riding plate of consid- 
erable area should always be placed 
on top of the brick-work for the lugs 
to rest upon; and all but one pair, be 
there many or few, should be provided 
with friction rollers. There should 
be a liner inside of the boiler beneath 
every supporting lug. It should be 
riveted at the corners, independently 
of the rivets that hold the lug. 

Manholes should be kept as small 
as possible because of the cutting 
away of the boiler's proper strength. 
Oval 12" X 15" is a good size, and 
while very large men cannot enter 
them, those considerably above the 
average girth can do so by raising 
their arms above their heads. Where 
the bracing does not take up so much 
room as to prevent access, the ring 
should invariably be put inside both 



192 BOILER MAKING. 

for strength and for convenience in 
calking. It is hardly necessary to say 
that the plate should be inside so that 
the pressure of the steam will help to 
keep the joint tight. Where a soft 
gasket (rubber, asbestos, and the like) 
is used, it is not necessary to haye the 
joint machined if fairly straight and 
smooth. The plate should have two 
handles, whether there be two bolts or 
one. No one who has not wrestled 
with a single-handled plate can con- 
ceive the amount of exasperation 
caused by it. Both handles and bolts 
can and should be cast into the plate, 
the bolt having a roughened head 
being held in a generous boss. 

Hand holes do not need a ring, but 
make their seating directly upon the 
plate. They should never be used 
where the seating is of necessity part- 
ly curved and partly flat, as it requires 
the greatest amount of patience and 
trouble to get them tight, and are a 
constant annoyance forever. 



FITTINGS. 193 

Mud plugs should be used in such 
places. These should be quite taper- 
ing, and, when new, should make the 
joint when the points have just shown 
through. The full length should be 
two and a half to three times the 
thickness of the plate to allow for re- 
tapping in case the thread of the hole 
is injured by the bars when cleaning. 

Fusible or safety plugs should be 
placed just on the line where the fire 
reaches highest and can play directly 
upon them : in a tubular boiler, in the 
back uptake, central, and just above 
the tubes-; in boilers of the locomo- 
tive type, in the fire-box crown, not 
far from the tube plate. It is desira- 
ble in such a situation that there be a 
cleaning hole opposite it so that it can 
be cleaned of scale or mud, which is 
apt to cover it there. Scale frequently 
(with bad water) forms so hard and 
thick, that although the tin may be 
melted out of the plug no water or 
steam can get through, in which case 



194 



BOILER MAKING. 



it might better be termed a " danger 
plug" instead of safety plug. 

The best, material for filling safety- 
plugs is "Banca tin," unalloyed. 

The hole in the plug should be taper- 
ing, with the large end outward so 



Fig., 131 




.. J , , , : \ 



as to present the least obstruction to 
the fused metal when it starts. Fig- 
ure 131 is a full-sized section of a plug 
that has given good service wherever 
used. 

Holes for gauge cocks should be 



FITTINGS. 195 

cut so that there will be not less than 
'2-J" height between the highest point 
reached by the fire and the lowest cock. 
3" is a better figure, because of de- 
fects in making and setting the boiler. 

All holes tapped for removable fit- 
tings should be tapering to allow the 
joint to be made in the thread. The 
joint should never be made with a 
shoulder in such cases, for but very 
few removals will destroy the thread 
so that it will, not draw up, whereas 
if it depends on the tapering thread 
it becomes compressed, and in conse- ' 
quence has a greater endurance. 

Gaspipe taps are about the best 
thing for such work in the smaller 
sizes, but while the taper and diame- 
ter of the larger sizes are convenient, 
the pitch of the thread is too coarse. 
It should never be greater than eleven 
and a half per inch to insure good 
work. Less than three threads in the 
plate is very unreliable. 



- XVIII. 

TESTING. 

There are various methods of test- 
ing boilers before leaving the .shop, 
and each has its adherents, though it 
would seem that the ideal test is that 
one which approaches closest to the 
conditions of actual service. Save 
for those with internal fire-boxes, this 
is of course impracticable; but for 
such it is the proper thing. 

The distortion caused by the local- 
ization of the intense Jieat shows at 
once all the little leaks and weak 
spots, which would otherwise cause 
words of cerulean tint to float around 
the fire-door during the boiler's in- 
fancy. The only disadvantage of this 



TESTING. 197 

method is the heat arising from the 
ashes and grate bars after the fire is 
drawn, which makes it almost impos- 
sible for the men to enter. However, 
this can be obviated by using a tem- 
porary knockdown grate, which may 
be hauled out with a poker or other 
hooked instrument. To catch the 
ashes a plate of light iron can be run 
under the fire-box, if the box be of 
the open bottom variety, which can 
be pulled out before the men enter. 
The same thing can be done with a 
close bottom if care is taken not to fit 
it too close. The warping caused by 
the heat will fasten it in otherwise. 

The cold water, or hydrostatic test, 
is decidedly hurtful, except in the 
hands of the most careful. The vi- 
brations caused by the sudden start- 
ing and stopping of the flow of water 
from the pump is only too apt to 
" rattle" the boiler to such an extent 
that what was in reasonably fair con- 
dition will be worse than the poorest. 



198 BOILER MAKING. 

Where sufficient draught cannot be 
had to produce a service test recourse 
may be had to a warm-water pressure. 
This is done by completely filling the 
boiler with water. This filling must 
be done from the highest point, so as 
to leave no contained air. Or if 
water is taken from a hydrant, leave 
the safety-valve open until the water 
is well out of it. Air gives no show 
when leaking through the joints as 
water will. Build but a light fire, 
and shortly the boiler will give indi- 
cations of labor. Great care must be 
taken in working the fire in this test, 
as the expansion of the water is posi- 
tive, and unlike steam is inelastic. 
It is both powerful and rapid when 
once it begins, being but slightly less 
than 5 cubic feet for every hundred 
contained by the boiler between the 
temperatures of 32 and 212 , or very 
nearly -^ cubic foot for every degree 
of heat. 

The advantage of this over the 



TESTING. 199 

cold-water pump test is that it is 
even and constant, consequently there 
is no shock to " rattle" the boiler. 

Frequently, it will be noticed that 
quite a number of leaks will show, 
from the bare weight of the water 
about the lower part of the boiler. A 
few of such leaks will close up as the 
heat is raised, but it is much better 
to close them all as they show than to 
wait and find out after the boiler is 
heated. The work is disagreeable 
enough at the best, and a little time 
lost in closing such little cold-water 
affairs will more than repay itself. 

Another method is to connect the 
boiler to a stationary one in which the 
steam is raised. Sometimes steam is 
taken from the shop-boiler, but this 
has a bad effect on the machinery, 
and besides, it requires an extra 
strength in a large boiler that is of 
no other use. A small auxiliary 
boiler, with capacious grate and large 
heating surface, to be used only for 



200 BOILER MAKING. 

heating purposes, is an indispensabil- 
ity in all shops where good work is 
done. 

Fill the boiler to be tested about 
one third full of water before blowing- 
Fig. 132 




in the steam. Much more or less 
will add considerably more to the 
quantity of steam required from the 
fired boiler, and steam means fuel. 

Barring a service test, the best 
practical method now employed is by 



use of the " Little Giant" boiler-test- 
ing apparatus, shown in figure 132, 
which fills the boiler with hot water 
and then applies the pressure gradu- 
ally, without shock, and holds it there. 

The arrangement is a combination 
of two distinct instruments: the upper 
one in the cut is an ordinary injector 
which fills the boiler ; the lower one 
is used for raising the pressure. 

In setting up this apparatus, con- 
nect 7 to the steam and 8 to the 
water pipes, while 9 leads to the 
boiler to be tested. It must be kept 
in mind that as this is not a "lifting" 
injector, the water must flow freely 
to it. 

To operate, move 1 to B, then turn 
on the water full. Next open valve 
3 gradually, until wide open. When 
the boiler is full close it (3) agair». 
To apply^ the pressure, move lever 1 
to a perpendicular position, as shown 
in the cut. When the water flows 
from the overflow 4, open the valve 



202 BOILER MAKING. 

2 gradually until wide open. Then 
if steam or water shows at the over- 
flow 4, regulate by moving the lever 
i toward A or B, as may be required. 
The pressure obtained will be indi- 
cated by the gauge. To fix the pres- 
sure, screw handle 5 up or down — 
down to increase, up to release. 

These instruments are made regu- 
larly to produce any pressure desired 
up to three times the initial steam 
pressure used, and if required can be 
made to go much higher. 

There should, invariably, be a 
gauge on the boiler under test, and - 
this gauge should be so placed as to 
be entirely out of the way of the in- 
flowing steam . or water — whichever 
is used. It is highly important that 
such gauges be accurate and reliable. 
Frequent test should be made of 
them. Straining from the high pres- 
sures put upon them is apt to weaken 
them, and in consequence there is not 
nearly so much pressure on the boiler 



TESTING. 203 

as they indicate. Should they happen 
to indicate, say, 100 lbs. when there 
was but 70 lbs., and the boiler is fixed 
up right and tight to all appearances, 
when in fact it is not, when put in 
service there is a woful time for 
maker or user, or mayhap both. 



XIX. 

ORDERING" STOCK. 

The first thing to be done on re- 
ceipt of the drawing is to make up a 
bill of materials requisite. This in- 
cludes, besides the plating, tubes (if 
called for), rivets, stay bolts and rods, 
plate and bars for stays, bar iron for 
water-legs, etc. 

The plate iron should be gotten out, 
as it requires some time to get it from 
the mill when it is rolled to size. There 
are standard sizes of plates kept in 
stock, but it is rarely that they will 
cut to the size wanted without con- 
siderable waste. It would be well to 
lay the boiler full size, if of irregular 
shape, thereby checking the drawing 
and reducing the chances of keeping 



ORDERING STOCK. 



205 



odd plates in stock. In getting up 
•this bill, keep such plates as are of the 
same material and thickness together. 
Give also each item a specific mark, 
either letter or number, irrespective 



H 



i Back Head Ex. Fl. 



|87Vs/55 



'50 



yV-\ P fTr\ 

x 49l 2 \sketch\ 



of the number of plates to each. This 
will prove very convenient in case of 
dispute, as the particular item can be 
identified at once. 

Mg; i'34 



V 



Plates of other than rectangular or 
circular shape must have a little fig- 
ured sketch accompanying. In the 
dimensions given for irregular shapes 
generally the two principal ones each 
way are given. Figure 134 is the 
sketch of the back head of a locomo- 



206 BOILER MAKING. 

tive boiler. The item accompanying 
it is given in full. 

Always give that dimension first 
that runs the direction in which the 
plate is to be bent. This is absolutely 
necessary only in lower grades than 
extra flange. With extra flange and 
higher grade it is not so requisite, be- 
cause such are supposed to be capa- 
ble of bending in any direction. Yet, 
if it is not necessary in high grade 
stock, it is well to make a regular 
thing of it, and there will be less 
chance of missing it when ordering 
low grade. In cutting out plates in 
the mil], the dimension given first is 
laid off in the direction in which the 
plate passed the rolls, and as in low 
grade stock that is the direction in 
which the fibers form, its importance 
is self-evident. As an example, take 
the welt plates for a butt-jointed seam ; 
if it is written, say, 4 plates — shell — 
.50X ioixf, you will surely have 
stock that 'will inevitably split on 



ORDERING STOCK. 207 

bending; but if written, 4 plates — 
shell — 10J X 50 X |, there is little fear 
of such consequences. 

Long rectangular .plates may be 
ordered very closely to the finished 
width, but an inch or two should be 
allowed in the length. The squares 
used in rolling mills are very apt to 
be something else. Allow plenty of 
trimming on irregularly shaped plates, 
as it is much better to lose a little in 
waste than to risk a great deal. 

Rivets being sold by the pound, ir- 
respective of their size, it necessitates, 
after determining the number re- 
quired, calculating their weight. All 
manufacturers furnish tables of weight 
of 100 rivets; therefore, to find the 
weight required, divide the number of 
rivets by 100 and multiply by the 
weight given for that particular size 
and length. For example, seven hun- 
dred and fifty-four f" rivets 1 J" long 
will weigh 754 ~ 100 X 36.70 (see table 
at end of this book) = 276.7 pounds. 



208 BOILER MAKING. 

It is best to add about ten per cent to 
allow for waste by burning, bad driv- 
ing, etc. Call it in this case 300 
pounds. 

Round and flat iron can be ordered 
by the running foot. 



WEIGHT OF IRON AND STEEL PLATE. 209 



WEIGHT OF IRON AND STEEL 
PLATE. 



Thickness 


Iron. 


Steel. 










in 
Inches. 


Pounds 

per 
sq. foot. 


Pounds 

per 
sq. inch. 


Pounds 

per 
sq. foot. 


Pounds 

per 
sq. inch. 


Ys 


5 


05 


•0351 


5 


08 


•o353 


ft 


7 


58 


.0526 


7 


62 


.0529 


H 


10 


10 


.0701 


10 


16 


.0707 


TB 


12 


63 


.0877 


12 


70 


.0882 


¥a 


15 


16 


• 1053 


15 


24 


•i°57 


TS 


17 


68 


.1228 


17 


78 


.1235 


H 


20 


21 


.1403 


20 


32 


.1411 


& 


22 


73 


•1578 


22 


86 


.1588 


% 


25 


26 


•1754 


25 


40 


.1764 


H 


27 


79 


•193 


27 


94 


.1926 


% 


30 


3i 


.2105 


30 


48 


.2117 


H 


32 


84 


.228 


33 


02 


.2193 


% 


35 


37 


.2456 


35 


56 


.1636 


U 


37 


*9 


.2631 


38 


10 


.2646 


1 


40 


42 


.2807 


40 


65 


.2823 



BOILER MAKING. 



CONE-HEAD BOILER RIVETS. 

Weight per Hundred. 
HOOPES & TOWNSEND. 



Length. 


^£ inch. 


^ inch. 


H inch. 


% inch. 


% inch. 


8 75 


16.20 






% ;; 


9 


35 


17.22 










i 


IO 


00 


18.25 


21 


70 


26 


55 


zl 6 \\ 


IO 


70 


19.28 


23 


10 


28 


00 


iM ." 


ii 


40 


20.31 


24 


50 


29 


45 


l3 S " 


12 


10 


21.34 


25 


90 


30 


90 


% :: 


12 


80 


22.37 


27 


30 


.32 


35 


13 


5o 


23.40 


28 


70 


33 


80 


i "< 


14 


20 


24-43 


30 


10 


35 


25 


14 


90 


25.46 


31 


50 


36 


70 


2 " 


15 


60 


26.49 


32 


90 


38 


15 


zVs " 


16 


30 


27.52 


• 34 


30 


39 


60 


2 ¥t ! 


*7 


00 


28.55 


35 


70 


4i 


05 


2% 


17 


70 


29.58 


37 


10 


42 


50 


2^ " 


18 


40 


30.61 


38 


50 


43 


95 


2% " 


19 


10 


31.64 


39 


90 


45 


40 


2M " 

2 % ;: 


i9 


80 


32.67 


4i 


30 


46 


85 


20 


5° 


33-70 


42 


70 


48 


30 


3, , ., 


21 


20 


34-73 


44 


10 


49 


75 


sM " 


22 


60 


30-79 


46 


90 


52 


65 


3 ^ !! 


24 


00 


38.85 


49 


70 


55 


55 


sM " 


25 


40 


40.91 


52 


50 


58 


45 


4 w « £ 


26 


80 


42.97 


55 


30 


61 


35 


$ - 


28 


20 


45-03 


58 


10 


64 


25 


29 


60 


47.09 


60 


90 


67 


15 


4M " 


31 


00 


49 -15 


63 


.70 


70 


PS 


5 , , l« 


32 


40 


51.21 


66 


So 


72 


95 


5 J5 


33 


80 


53-27 


69 


20 


75 


85 


5 ^ 


35 


20 


55-33 


72 


00 


78 


75 


5M " 


36 


60 


57-39 


74 


80 


81 


65 


6 " 


33 


00 


59-45 


77 


60 


84 


55 


6)4 " 


40 


80 


63-57 


83 


3° 


90 


35 


7 " 


43 


60 


67.69 


88 


90 


96 


15 



TANK RIVETS. 



TANK RIVETS. 

Ntunber to the Potmd. 
HOOPES & TOWNSEND. 





ft 


in. 


M 


„. 


T 5 6 


in. 


%m. 




un. 


Diam. 


Diam. 


Diam. 


Length. 
















F. & 




F. & 




F. & 




F. & 








c.'s. 




c. s. 




c. s. 




c. s. 




R. H. 




R. H. 




R. H. 




R. H. 




% 


I6 5 


230 


103 


155 


67 


89 




TS 


153 


200 


92 


128 


58 


78 


35 




H 


135 


172 


81 


108 


SO 


69 


31 


46 


% 


Il8 


148 


71 


93 


44 


60 


27 


40 


H 


103 


129 


63 


80 


39 


53 


23 


35 


Vs 


92 


114 


56 


70 


35 


47 


21 


31 


i 


84 


102 


50 


62 


32 


42 


19 


27 


46 


77 


93 


46 


56 


30 


37 


18 


24 


Ai 


72 


85 


43 


5i 


28 


34 


17 


22 


i% . 


67 


78 


40 


47 


26 


31 


16 


21 


• 4* 


62 


72 


37 


44 


24 


29 


15 


20 


m 


58 


67 


34 


4i 


22 


27 


14 


19 


i% 


54 


62 


32 


38 


21 


25 ' 


13 


18 


i% 


5i 


58 


30 


35 


20 


23 


12 


17 


2 


48 


54 


29 


33 


19 


22 


11. 


16 



F. & R. H. indicates Flat and Round Heads. C. S. 
indicates Countersunk. • 



INDEX. 



[In looking for any subject having more than one 
word, look first for what appears to you to be the prin- 
cipal word, and if you do not find it under the initial 
letter of that word, try under that of the other.] 

PAGE 

Angle of calking edge 155 

Angle iron for brace feet 80, 82 

Annealing 115 

Annealing furnace 117, 118, 119 

Annealing without a furnace 116 

Anvil for forging crow-foot braces 134 

Back connection marine boiler 30 

Bad joint , 47 

Bar for holding on 53 

Bar iron, ordering 208 

Bars for crown plate of furnaces 70 

Beading tool 186 

Beading tubes, length to allow for i§2 

" Belpair" furnace 37 

Bending, cold 159 

Bending plate with large openings 162 

Bending test for plate 17 

Bent brace jaws 84 

Bill of materials 204 



214 INDEX. 

PAGE 

Blisters ■- . . , 43 

Block for holding on in narrow space 54 

Boiler forms , 20 

Boiler, turning over .. 172 

Bolts, clamping 168 

Bolts, crown sheet 68 

Bolts, manhole plate 192 

Brace feet 80 

Brace feet, flanged angle iron for 82 

Brace jaws , 77, 128 

Brace jaws, crooked 84 

Brace jaws, forging 128 

Braces and stays, direction of. 59 

Braces and stays, fitting 59 

Braces and stays, number and size 58, 85 

Braces, crow-foot 80, 134 

Braces, for large boilers 85 

Braces, pins for 78 

Bracing and staying. , 58 

Brands of iron plate 10, 12 

Bursting strength of cylinders 22 

Butt joints .' 26, 45 

Button rivet point 51 

Calking 175 

Calking, concave . . 176, 178 

Calking, evil effects of over 175 

Calking, styles of 175 

Calking tools 176, 180 



INDEX. 215 

PAGfi 

Cam lever for bending crown bars 125 

Castings for formers 93 

Cast iron 14 

Cast iron fittings 189 

Cast iron heads 14 

Cast iron pipe 189 

Cast iron pipe flanges 189 

Cast iron shrinkage strains 189 

Chain, jack, for setting up 166 

C. H. No. 1, Fire box 10, 11 

C. H. No. 1, Flange 10, n 

Circular heads 33 

Circular heads, trimming 157 

Clamping bolts 168 

Clamping plates for flanging 98 

Clamping sides of fire boxes 170 

Cocks, fitting holes for gauge 194 

Cocks, position of gauge 195 

Cold bending 159 

Cold bending plate with large openings 162 

Cold bending rolls 160 

Cold, effect of, on rivets 57 

Cold water, or hydrostatic test 197 

Combustion chambers 41, 42 

Compensating rings 3 1 

Concave calking 176, 178 

Conical rivet point 5 1 

Copper ferrules 182 

Copper fire boxes 9 



2l6 INDEX. 

PAGE 

Corners, smithing of plate. 122 

Corners, trimming of plate 157 

Corrosion of stays 61 

Counterboring tool 152 

Countersinking tool 51, 151 

Countersunk rivets 51 

Crane, traveling 164 

Crooked brace jaws 84 

Crow-foot brace 80, 134 

Crow-foot brace, anvil for forging 134 

Crow-foot brace, forging 134 

Crown bar 70 

Crown bar bolts 68 

Crown bar, cam lever for bending 125 

Crown bar, fitting 71 

Crown bar, former 124 

Crown bar, formula 73 

Crown bar heating furnace 126 

Crown bar slings 74 

Crown bar smithing 123 

Crown bar thimble 71 

Crown sheet bolts 68 

Curved crown bars , 123 

Cylinder, annealing 117 

Cylinder bursting strength 22 

Cylinder, external pressure on 25 

Cylinder, force to burst transversely 24 

Cylinder thickness 21 

Cylinder welding 111 



INDEX. 217 

PAGE 

Cylindrical boiler, setting up 174 

Cylindrical flues '. . 27 

Cylindrical form of boiler 20 

Die formula 147 

Dies for punches 147 

Direct fire the proper test 196 

Direction of stays and braces 59 

Disposition of stays and braces 58 

Distortion from heat 196 

Dome flanging 107 

Dome opening, bending plate with 162 

Dome, welted opening of 32 

Domes 31 

Domes, setting up 1 72 

Doors, furnace . , 40 

Drawing of the metal in flanging 105 

Dressing formers 05 

Drifting rivet holes to bring fair 54 

Drilled rivet holes , 56 

Drilling, etc 150 

Drilling machine 153 

Drills, twist' 150 

Driving rivets 52, 55 

Ductility of metal 10, 13 

Effect of cold on riveting 57 

Effect of overdriving on calking 175 

Elongation of iron in test 12 



2l8 INDEX. 

PAGE 

Elongation of steel in test >. . . . 10 

English method of welding plates 109 

Expanding tool 184 

Expanding tubes 183 

External pressure on cylinders 25 

Faces of punches 144 

Factor of safety 21 

Falls for hoisting and lowering 173 

Feet of braces So 

Fitting braces and stays 59 

Fitting crown bars 71 

Fittings 189 

Fittings, cast iron 189 

Fitting screwed stays 62 

Fire boxes, clamping in sides 170 

Fire boxes, copper 9 

Fire boxes, setting up 169 

Fire box, plumbing and lining 172 

Fire box rings, forging 135 

Fire box rings, slotting 137 

Fire door flange 93 

Fire, flanging 95 

Fi're welding 113 

Flanged plates, sling for ' 96 

Flanged tee for brace feet 81 

Flanged tee former 126 

Flanged tee-iron 127 

Flanged work, trimming 158 



INDEX. 219 

PAGE 

Flange fire 59 

Flange fire tuyere 95 

Flange former pattern 93 

Flange formers 92 

Flange heating 96 

Flange iron 16 

Flange iron testing 17 

Flange, C. H. No. 1 10 

Flange, radius of 92 

Flanges on cast iron pipes 189 

Flanging 92 

Flanging, clamping plate while 98 

Flanging domes. 107 

Flanging forge, height of 96 

Flanging gauge 104 

Flanging, holding down staves for 103 

Flanging mauls 100 

Flanging methods 92 

Flanging over anvil or block 103 

Flanging under black heat 102 

Flat ends 24 

Flat surfaces 33 

Flatter handles 101 

Flatters 101 

Flue joints, furnace 28, 35 

Flues, thickness of cylindrical. 27 

Flues, transverse joints 27, 28 

Forces to burst cylinder transversely. 24 

Forging brace jaws 128 



220 INDEX. 

PAGE 

Forging crow-foot brace 134 

Forging curved crown bars 123 

Forging fire box rings .* 135 

Forging flanged tee 127 

Former castings 93 

Former for flanging 92 

Former for smithing crown bars. J 24 

Forming brace jaws 132 

Forms of boilers 20 

Formula, circular heads 33 

Formula, crown bars 73 

Formula, cylinder to resist bursting 22 

Formula, force to burst cylinder. 24 

Formula, longitudinal strength of cylinder. 24 

Formula, punch dies 147 

Formula, riveted joints 48 

Formula, stays ; 61 

Formula, thickness of cylinder 2r 

Formula, thickness of cylindrical flues 27 

Furnace, annealing 117 

Furnace, ' • Belpair " '37 

Furnace doors 40 

Furnace for heating crown bars 126 

Furnace flue joints 28, 35 

Furnace plates . . . 42 

Furnaces 34 

Furnaces, locomotive 35 

Fusible plugs 193 

Fusible plugs, material for filling. 194 



INDEX. 221 

PAGE 

Gasket for manholes 192 

Gas-pipe taps 195 

Gauge cocks 194 

Gauge cocks, position of , 195 

Gauge cocks, taps for 195 

Gauge, flanging 104 

Gauge, testing 202 

Girth seam riveting 52 

Grate, temporary for testing 197 

Grooving 46 

Guarantee of strength 13 

Gusset stays „ 88 

Hammer, holding-on 53 

Hand holes . . . « 192 

Handles, manhole plate 192 

Hand riveting 53 

Heads 14, 34 

Heads, cast iron 14 

Heads, circular. ... 33 

Heads, trimming circular 157 

Heating crown bars 126 

Heating flanges « 96 

Heating rivets 53 

Heating steel 17, 114 

Heavy braces 85 

Heavy braces, turnbuckle for 86 

Heavy plate punching. . .. „ 143 

Height of flange forge 96 



222 INDEX. 

PAGE 

Hoisting and lowering boilers „ 172 

Holding-down staves for flanging 103 

Holding-on bar 53 

Holding-on block for narrow space 54 

Holding-on hammer 53 

Holes for tubes, punching 148 

Hollow screwed stays 65 

Hooks, porter, for handling plate 99 

Hornbeam, 100 

Hydrostatic test 197 

Injector for testing 200 

Inspectors' rate for iron 12 

Iron, cast 14 

Iron, elongation in test 12 

Iron for rivets 13 

Iron for stay bolts 13 

Iron plate 10 

Iron plate, brands of 10 

Iron plate, weight of 209 

Iron, refined II 

Iron, rolled tee 29 

. Iron, shell 11 

Iron, stay rod. 14 

Iron, tank ; 11, 12 

Iron, tensile strength II, 14 

Iron, testing flange 17 

Iron, U. S. Gov. inspector^' rate 12 

Iron, welding heat for 114 



INDEX. 223 

PAGE 

Jack chain for setting up 166 

Jaws of braces 77, 84, 127 

Jaws of braces, bent 84 

Joint, bad 46 

Joint, butted and welted 26, 45 

Joints, formulas for riveted 48, 49 

Joints, furnace flue .27, 28, 35 

Joints, lap 26, 44 

Joints, longitudinal 26 

Joints, riveted 44, 47 

Joints, table of proportions of riveted. . . .49, 50 

Joints, transverse of flues 27, 28 

Joints, welted 45 

Lamination of plates 15 

Lap joints 26, 43 

Lap welded tubes 30 

Lap welding plates no 

Large braces 85 

Large opening, cold bending plate with. . . . 162 

Large tubes, setting 187 

Leaks, small t 199 

Length to allow for beading 182 

Lining up 167 

Lining up with straight edge 168 

"Little Giant " boiler testing apparatus. . . 200 

Locomotive furnaces 36 

Locomotive wagon top 36 

Longitudinal lap joint 26 



2 24 INDEX. 

PAGE 

Longitudinal strength of cylinders 24 

Long screwed stay 65 

Long screwed stay, support for 67 

Long screwed stay, tap for 66 

Lowering with a fall 173 

Lugs for crown bar slings 76 

Lugs, riding plate for supporting 191 

Lugs supporting, for cylindrical boilers .... 190 

Machines for driving rivets 52 

Machines for trimming plate. 156 

Manholes 31, 162, 191 

Manholes, gaskets for 192 

Manhole opening, bending plate at 162 

Manhole plate bolts 192 

Manhole plate handles 192 

Manholes, size of 191 

Marine back connection. 31 

Marine boiler* 34 

Materials 9 

Materials, bill of 204 

Material for filling safety plugs 194 

Materials, testing 14 

Marking-off for punching 140 

Mauls for flanging 100 

Measure for length of tubes , . 181 

Methods of flanging 92 

Methods of testing 196 

Mud plugs 193 



INDEX. 225 

PAGE 

Narrow water spaces 37 

Narrow water space stays 60 

N. P. U. iron 12 

Number and size of braces and stays, ..... 58 

Openings for domes 31, 33 

Ordering bar iron 204, 208 

Ordering plates. . . . 3 204 

Ordering rivets. 207 

Ordering Stock 204 

Overdriving in calking. 175 

Pattern, flanging former 93 

Pine iron 12 

Pins, brace 78 

Pipe flanges, cast iron 189 

Pipes, cast iron 189 

Plate, brands of iron 10 

Plate bending test , 17 

Plate edge trimming machine.. .„ 156 

Plate, iron . . . „ 10 

Plate,, ordering 204 

Plate, riding, for supporting lugs 191 

Plate, punching heavy 143 

Plate, smithing corners 121 

Plate, steel 10 

Plate, testing 15 

Plate test, table of angles bending 16 

Plate, weight of iron and steel 209 

Plate welding 108 



2 26 INDEX. 

PAGE 

Plate, working test 16 

Plates furnace 42 

Plates, lap welding no 

Plumbing fire box 172 

Plugs, fusible or safety 193 

Plugs, material for filling safety 194 

Plugs, mud , 193 

Pockets in fire box sides 137 

Points of rivets , 50 

Porter hooks 99 

Position of gauge cocks 195 

Power riveting 52 

Pressure, external on cylinder 25 

Proportions of riveted joints, table, 49 

Punch die, formula 147 

Punch die '. . 147 

Punch faces , 144 

Punched hole, properly fitted 149 

Punching 138 

Punching heavy plate .- 143 

Punching holes for tubes 148 

Punching, marking off for 140 

Punching table 139 

Punch, spiral shearing. 144 

Punch stocks 146 

Radius of flanges t 92 

Record of strength 13 

Rectangular boilers 34 



INDEX. 227 

PAGE 

Refined iron 11 

Riding plate for supporting lugs 191 

Rimers 54, 154 

Rivet driving 55 

Riveted joints 44 

Riveted joints, designing 47 

Riveted joints, formulas 48, 49 

Riveted joints, table of proportions 49, 50 

Rivet holes, drilled 56 

Rivet holes, drifting to bring fair 54 

Riveting 50 

Riveting, effect of cold on 57 

Riveting girth seams. 52 

Riveting, hand 53 

Riveting, power 52 

Riveting with a snap 56 

Rivet iron 13 

Rivet iron strains 13 

Rivet points 50 

Rivets, heating power driven 53 

Rivets, heating hand driven ; 54 

Rivets, ordering 207 

Rivets, steel 13 

Rivets, weight of, table 210, 211 

Rivet, test 19 

Rolled tee iron 29, 81 

Rolling plate, cold 161 

Rolls for bending cold 160 

Rounding tool, tube hole 153 



228 INDEX. 

PAGE 

Safety, factor of 21 

Safety plugs 193 

Safety plugs material for filling 194 

Screwed stays., 60, 65 

Screwed stays, fitting „ 62 

Screwed stays, formula . 61 

Screwed stays, hollow 65 

Screwed stays, support for long 67 

Screwed stays, taps for .63, 66 

Screwed stays, wrench for 64 

Setting copper ferrules 183 

Setting large tubes 187 

Setting screwed stays, wrench for 64 

Setting Tubes 181 

Setting up u 164 

Setting up cylindrical boilers 165, 174 

Setting up domes 172 

Setting up fire boxes 169 

Setting up floor . 164 

Setting up locomotive boilers 169 

Shell iron. . ' 11 

Shrinkage strains in cast iron 189 

Single riveted lap-joint 44 

Size and number of braces and stays 58 

Size of crown bar 73 ( 

Size of manholes 191 

Sligo iron 12 

Slings, crown bar 74 

Slings for carrying plates 96 



INDEX. 229 

PAGE 

Slotting fire box rings 137 

Small leaks 199 

Smithing 121 

Smithing crown bars , 123 

Smithing fire box rings. 135 

Smithing plate corners 121 

Snap, riveting with 56 

Special brands of plate 12 

Spherical form of boiler 20 

Spiral shearing punch 144 

Stay bolt iron, tensile strength 13 

Stay bolt iron, test 19 

Stay bolts 60 

Stay bolts, crown sheet 68 

Staying and bracing 58 

Stay rod iron 14 

Stays and braces, direction of . . c 59 

Stays and braces, fitting 59, 62 

Stays and braces, number and size 58 

Stays, corrosion of 61 

Stays, fitting screwed 62 

Stays, formula 61 

Stays, gusset 88 

Stays, hollow screwed 65 

Stays, long screwed 65 

Stays, taps for screwed . . . . 62, 66 

Stays, throat plate 87 

Stays through plate at angle 67 

Stays, support for long 67 



230 INDEX. 

PAGE 

Stays, wrench for screwed 64 

Staves for holding down while flanging 103 

Steady pins for flanging 95 

Steel, elongation of in test 10 

Steel, heating 17, 114 

Steel plate 10 

Steel plate, weight of, table 209 

Steel rivets 13 

Steel rivets, tensile strength of 13 

Steel, strength of 10 

Steel, testing 17 

Steel, test piece 10 

Steel, welding heat 114 

Stiffening flat surfaces without bracing 83 

Stock ordering 204 

Stocks, .punch 146 

Stop-water 27, 175 

Straight edge, lining up with 168 

Strains On rivet iron 13 

Strength of clyinder 22, 24 

Strength of steel 10 

Styles of calking 175 

Supporting lugs 190 

Supporting lugs, riding plate for 191 

Support, long screwed stay 67 

Surfaces, flat stiffened without bracing .... 83 

Swedging tubes 183 

Table, angles for bending plate in test 16 

Table for front of punching machine 140 



INDEX. 231 

PAGE 

Table, proportions of riveted joints 49, 50 

Table, weight of cone head rivets 210 

Table, weight of iron and steel plate 209 ■ 

Table, weight of tank rivets 211 

Taking measure for length of tubes 181 

Tank iron II, 12 

Tank rivets, weight of. ; 211 

Taps for screwed stays 62, 66 

Taps, gas pipe 195 

Taps, gauge cock 195 

Tee-iron for brace feet 81 

Tee iron flanged 81, 126 

Tee iron rolled 29, 81 

Templet, for marking off for punching 142 

Temporary grate for testing 197 

Tensile strength 9, 12 

Tensile strength of iron 11 

Tensile strength of stay-bolt iron 13 

Tensile strength of stay-rod iron 14 

Tensile strength of steel 10 

Tensile strength of steel rivets 14 

Test gauge 202 

Test by steam from another boiler 199 

Test by steam, injector forced 200 

Test, hydrostatic or cold water 197 

Test, warm water 198 

Test for plate, bending 17 

Testing 196 

Testing, filling boiler for. 198, 200 

Testing flange iron 17 



232 INDEX. 

PAGE 

Testing materials 14 

Testing plate 15 

Testing, temporary grate for 197 

Test piece, steel 10 

Test rivet to. 

Test, stay-bolt iron 13, 19 

Test, steel 17 

Test, tube 18 

Thickness of cylinder 21 

Thickness of cylindrical flues 27 

Thickness of plate, testing 15 

Thimble, crown bar 71 

Throat plate .- . . 105 

Throat plate stays 87 

Tool for beading tubes 186 

Tool for counterboring 152 

Tool for countersinking 51, 151 

Tool for expanding tubes 184 

Tool for holding tubes in place 184 

Tool for rounding tube holes 153 

Toughness of metal 10, 13 

Transverse joints of flues 27 

Traveling crane 164 

Trimming 155 

Trimming circular heads 157 

Trimming corners 157 

Trimming flanged work 158 

Tube holes, punching 148 

Tubes. . , 9, 18, 30, 181 



INDEX. 233 

PAGE 

Tubes, expanding 183 

Tube, setting 181 

Tubes,' setting large 187 

Tubes, small lap-welded 30 

Tubes, swedging 183 

Tubes, taking measure for length 181 

Tubes, tool for beading . . . , 186 

Tube test ' 18 

Turnbuckle for heavy braces 86 

Turning over boilers 172 

Tuyere, flanging fire 95 

Twist drill 150 

U. S. Gov. inspectors' rate for iron 12 

Wagon top 36 

Warm water test 198" 

Water leg bottoms 38 

Water spaces, narrow 37 

Water space stays, narrow 60 

' Weight of iron and steel plate 209 

Weight of rivets * 210, 211 

Welding cylinders in 

Welding fire 113 

Welding heat 114 

Welding jaws to braces 128 

Welding plates 108 

Welding plates, English method 109 

Welted joints 45 

Wrench for screwed stays 64 



